An investigation of the behaviour and biology of the Citrus Mussel Scale, Lepidosaphes Beckii (Newm.)
- Authors: Hulley, Patrick Elliot
- Date: 1961
- Subjects: Lepidosaphes beckii , Citrus -- Diseases and pests -- South Africa , Scale insects -- Larvae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5912 , http://hdl.handle.net/10962/d1015459
- Description: The citrus industry is subject to a number of serious insect pests. Of these, the most important is a sedentary group known as the Armoured Scale Insects (Diaspididae). Ebeling (1950) states that they are of greater economic importance to the industry than all the other pests put together. A great deal has been published on various aspects of the biology, ecology and control of the Diaspididae, much of the work appearing in the books of Quayle (1938), Ebeling (1950) and Bodenheimer (1951). It is very noticeable, however, that the study of the active larvae, or "crawlers", of these insects has been relatively neglected. This lack of work on crawlers is surprising, since they are the only distributive stage in the life cycle of the species. The adult male is also free-living during its brief life span, but takes no part in the actual distribution of the species. It is the position of the female Scale Insect which is important in determining the further spread of the species, since this is the point from which subsequent crawlers will start out on their wanderings. The stage in the life cycle responsible for the position of the female is, of course, the crawler. The crawler is also responsible for the parallel distribution of the male Scales, so that the female can be fertilised. The role of the adult male is confined to the maintenance of the gene flow. From an economic point of view it seems desirable that a complete study be made of the biology of this distributive stage of these important pests.
- Full Text:
- Date Issued: 1961
- Authors: Hulley, Patrick Elliot
- Date: 1961
- Subjects: Lepidosaphes beckii , Citrus -- Diseases and pests -- South Africa , Scale insects -- Larvae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5912 , http://hdl.handle.net/10962/d1015459
- Description: The citrus industry is subject to a number of serious insect pests. Of these, the most important is a sedentary group known as the Armoured Scale Insects (Diaspididae). Ebeling (1950) states that they are of greater economic importance to the industry than all the other pests put together. A great deal has been published on various aspects of the biology, ecology and control of the Diaspididae, much of the work appearing in the books of Quayle (1938), Ebeling (1950) and Bodenheimer (1951). It is very noticeable, however, that the study of the active larvae, or "crawlers", of these insects has been relatively neglected. This lack of work on crawlers is surprising, since they are the only distributive stage in the life cycle of the species. The adult male is also free-living during its brief life span, but takes no part in the actual distribution of the species. It is the position of the female Scale Insect which is important in determining the further spread of the species, since this is the point from which subsequent crawlers will start out on their wanderings. The stage in the life cycle responsible for the position of the female is, of course, the crawler. The crawler is also responsible for the parallel distribution of the male Scales, so that the female can be fertilised. The role of the adult male is confined to the maintenance of the gene flow. From an economic point of view it seems desirable that a complete study be made of the biology of this distributive stage of these important pests.
- Full Text:
- Date Issued: 1961
An investigation of the polarization of solar radio noise
- Authors: Verschuur, Gerrit L.,1937-
- Date: 1961
- Subjects: Solar radio emission , Polarimetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5547 , http://hdl.handle.net/10962/d1013441
- Description: CHAPTER I A description of the sun and the type of radio radiation it emits is given. The relation that exists between this and other events occurring on the sun's surface is studied. CHAPTER II The literature dealing with the origin of solar radio noise is reviewed. CHAPTER III The method of specifying polarized radiation and the effect of a magneto- ionic medium on such radiation is discussed. The possible origin of the polarization of solar radio noise is examined and the literature relating to this and to the observations of polarization of solar noise is reviewed. A short outline of the methods used in measuring polarization is given. CHAPTER IV A detailed outline of the construction of a polarimeter is given together with full circuit diagrams and illustrative photographs. CHAPTER V A brief discussion of the operation of the polarimeter, the results obtained and suggestions for its future operation is given.
- Full Text:
- Date Issued: 1961
- Authors: Verschuur, Gerrit L.,1937-
- Date: 1961
- Subjects: Solar radio emission , Polarimetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5547 , http://hdl.handle.net/10962/d1013441
- Description: CHAPTER I A description of the sun and the type of radio radiation it emits is given. The relation that exists between this and other events occurring on the sun's surface is studied. CHAPTER II The literature dealing with the origin of solar radio noise is reviewed. CHAPTER III The method of specifying polarized radiation and the effect of a magneto- ionic medium on such radiation is discussed. The possible origin of the polarization of solar radio noise is examined and the literature relating to this and to the observations of polarization of solar noise is reviewed. A short outline of the methods used in measuring polarization is given. CHAPTER IV A detailed outline of the construction of a polarimeter is given together with full circuit diagrams and illustrative photographs. CHAPTER V A brief discussion of the operation of the polarimeter, the results obtained and suggestions for its future operation is given.
- Full Text:
- Date Issued: 1961
Investigation of the formation of complexes between selected organic compounds and the chlorides and sulphates of chromium
- Authors: Ellis, Melville John
- Date: 1961
- Subjects: Organic compounds , Chromium compounds , Chlorides , Sulfates
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4466 , http://hdl.handle.net/10962/d1011744 , Organic compounds , Chromium compounds , Chlorides , Sulfates
- Description: Some properties of soluble chromium complexions containing coordinated aliphatic acids have been studied. The work falls naturally into two sections. In the first, the coordination of a series of ⊄, β and⊁amino acids by chromium chloride has been studied by physical methods. The tanning action of chromium chloride in the presence of these amino acids has also been studied. The absorption spectra of the complexes were similar to those reported previously for trivalent chromium solutions, having two pronounced maxima in the visible region. From the variations in these absorption maxima, it is suggested that the absorption maximum in the 580 m u region is influenced by coordination of the chromium with the ligand, while the maximum in the 420 m u region is also affected by the olation of the basic chromium salts. The spectrophotometric evidence indicates that raising the pH or the concentration of the ligand in the solution increases the amount of coordination, and further, that the tendency for coordination increases as the hydrocarbon chain separating the carboxyl and amino groups becomes longer. This suggests that tho stability of the complex is not dependent on chelate ring formation, but is influenced by the pK₁ value of the carboxyl group of the . ligand. Potentiometric titrations support the hypothesis that only the carboxyl group is coordinated, to an extent depending on its pK₁ value, since the curves have shown that the amino group is still free to titrate. Paper electrophoresis has shown that all the complexes prepared were cationic, indicating that the amino acids were coordinated as dipolar ions. The tanning action of the masked chromium solutions has confirmed the deductions made from the physical measurements. Increasing the amount of amino acid added to the solution lowered the chromium fixation and the hydrothermal stability of the leather, and further, that for solutions at the same pH containing the same amount of masking agent, tanning action was least for the ⊁ amino acid and greatest for the ⊄ amino acids. Comparison of the present data with the corresponding results obtained with chrome alum solutions showed that coordination of the amino acids was greater in the case of the chromium chloride solutions. The second section of the experimental work was an investigation of the coordination of substituted acetic and propionic acids by chromium chloride and chromium sulphate. Spectrophotometric and potentiometric methods were applied and the various solutions were also used in miniature tanning experiments. Certain difficulties were encountered in the preparation of some of the complexes, and it was not possible to carry the work to a point where conclusive results could be obtained. Nevertheless, the work reported suggests that chelate ring formation occurs in the coordination of hydroxy-carboxylic acids, resulting in exceptionally high stability of the complex. In the case of the other ligands, containing amino, chloro and bromo groups, as well as with acetic and propionic acids, the results suggest that coordination involves the carboxyl group only, and that the pY value of this group is an important factor determining the stability of the complexes.
- Full Text:
- Date Issued: 1961
- Authors: Ellis, Melville John
- Date: 1961
- Subjects: Organic compounds , Chromium compounds , Chlorides , Sulfates
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4466 , http://hdl.handle.net/10962/d1011744 , Organic compounds , Chromium compounds , Chlorides , Sulfates
- Description: Some properties of soluble chromium complexions containing coordinated aliphatic acids have been studied. The work falls naturally into two sections. In the first, the coordination of a series of ⊄, β and⊁amino acids by chromium chloride has been studied by physical methods. The tanning action of chromium chloride in the presence of these amino acids has also been studied. The absorption spectra of the complexes were similar to those reported previously for trivalent chromium solutions, having two pronounced maxima in the visible region. From the variations in these absorption maxima, it is suggested that the absorption maximum in the 580 m u region is influenced by coordination of the chromium with the ligand, while the maximum in the 420 m u region is also affected by the olation of the basic chromium salts. The spectrophotometric evidence indicates that raising the pH or the concentration of the ligand in the solution increases the amount of coordination, and further, that the tendency for coordination increases as the hydrocarbon chain separating the carboxyl and amino groups becomes longer. This suggests that tho stability of the complex is not dependent on chelate ring formation, but is influenced by the pK₁ value of the carboxyl group of the . ligand. Potentiometric titrations support the hypothesis that only the carboxyl group is coordinated, to an extent depending on its pK₁ value, since the curves have shown that the amino group is still free to titrate. Paper electrophoresis has shown that all the complexes prepared were cationic, indicating that the amino acids were coordinated as dipolar ions. The tanning action of the masked chromium solutions has confirmed the deductions made from the physical measurements. Increasing the amount of amino acid added to the solution lowered the chromium fixation and the hydrothermal stability of the leather, and further, that for solutions at the same pH containing the same amount of masking agent, tanning action was least for the ⊁ amino acid and greatest for the ⊄ amino acids. Comparison of the present data with the corresponding results obtained with chrome alum solutions showed that coordination of the amino acids was greater in the case of the chromium chloride solutions. The second section of the experimental work was an investigation of the coordination of substituted acetic and propionic acids by chromium chloride and chromium sulphate. Spectrophotometric and potentiometric methods were applied and the various solutions were also used in miniature tanning experiments. Certain difficulties were encountered in the preparation of some of the complexes, and it was not possible to carry the work to a point where conclusive results could be obtained. Nevertheless, the work reported suggests that chelate ring formation occurs in the coordination of hydroxy-carboxylic acids, resulting in exceptionally high stability of the complex. In the case of the other ligands, containing amino, chloro and bromo groups, as well as with acetic and propionic acids, the results suggest that coordination involves the carboxyl group only, and that the pY value of this group is an important factor determining the stability of the complexes.
- Full Text:
- Date Issued: 1961
John X. Merriman : the making of a South African statesman (1869-1878)
- Authors: Gruber, R F J
- Date: 1961
- Subjects: Merriman, John Xavier, 1841-1926 , Statesmen -- South Africa -- Biography , South Africa -- Politics and government -- 1836-1909
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2623 , http://hdl.handle.net/10962/d1015002
- Description: With the possible exception of Hofmeyr and Schreiner, there is no Cape statesman whose career raises more tantalising questions than that of John X. Merr1man. Last Prime Minister of the Cape Colony, doyen of Parliamentarians, brilliant orator, versatile administrator, veteran politician, his public life stretched across fifty-five years of south African History. He entered upon it before the grant of Responsible Government, the discovery of diamonds and gold, and the awakening. of Afrikaner Nationalism; he departed from it on the eve of the Statute of Westminster, the establishment of Iscor and the coming to power of Hertzog and Malan. His contemporaries looked upon him as a man of immense knowledge and olympian ability. In the eyes of many his position as leader of the largest and oldest settled community in South Africa, not to mention his role as heir to the Cape tradition, made him the natural choice as first Prime Minister of the Union he had helped to establish. He was not called to office. Barely seventy, in the full maturity of his years, he withdrew trom active political leadership in the country of his adoption. He is hardly remembered today. This thesis seeks to contribute something to an understanding of the man and an assessment of his qualities by a study of his formative years. It attempts both to reconstruct his personality and analyse the nature of his statesmanship - not only by an examination of the role he played in the years under review, but also by an assessment of the part he failed to play. For this purpose both the structure of Cape politics and the ramifications of the various problems that presented themselves have been explored in greater detail than might otherwise have been the case.
- Full Text:
- Date Issued: 1961
- Authors: Gruber, R F J
- Date: 1961
- Subjects: Merriman, John Xavier, 1841-1926 , Statesmen -- South Africa -- Biography , South Africa -- Politics and government -- 1836-1909
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2623 , http://hdl.handle.net/10962/d1015002
- Description: With the possible exception of Hofmeyr and Schreiner, there is no Cape statesman whose career raises more tantalising questions than that of John X. Merr1man. Last Prime Minister of the Cape Colony, doyen of Parliamentarians, brilliant orator, versatile administrator, veteran politician, his public life stretched across fifty-five years of south African History. He entered upon it before the grant of Responsible Government, the discovery of diamonds and gold, and the awakening. of Afrikaner Nationalism; he departed from it on the eve of the Statute of Westminster, the establishment of Iscor and the coming to power of Hertzog and Malan. His contemporaries looked upon him as a man of immense knowledge and olympian ability. In the eyes of many his position as leader of the largest and oldest settled community in South Africa, not to mention his role as heir to the Cape tradition, made him the natural choice as first Prime Minister of the Union he had helped to establish. He was not called to office. Barely seventy, in the full maturity of his years, he withdrew trom active political leadership in the country of his adoption. He is hardly remembered today. This thesis seeks to contribute something to an understanding of the man and an assessment of his qualities by a study of his formative years. It attempts both to reconstruct his personality and analyse the nature of his statesmanship - not only by an examination of the role he played in the years under review, but also by an assessment of the part he failed to play. For this purpose both the structure of Cape politics and the ramifications of the various problems that presented themselves have been explored in greater detail than might otherwise have been the case.
- Full Text:
- Date Issued: 1961
Studies on the neuro-physiology of a free-living Platyhelminth
- Authors: Boyle, Sheila A
- Date: 1961
- Subjects: Platyhelminthes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5902 , http://hdl.handle.net/10962/d1013541
- Description: From Resumé: The general picture of the physiology of invertebrate neuro-muscular systems as contrasted with the classical vertebrate system is presented and it is clear that one of the groups least investigated is the Phylum Platyhelminthes. An examination of the properties of the myo-neural system of a platyhelminth should be of interest, not only in itself, but also because of a possible relationship with the coelenterates, whose neuro-muscular system has been fairly extensively investigated. The aim of the present work was to determine some of the properties of the myo-neural system of a platyhelminth, and more especially those which would make possible a comparison with the myo-neural systems of other invertebrate phyla, and most particularly with the coelenterates. A preparation consisting of an entire decerebrate animal was used. The general anatomy of the musculature and basic plan of the nervous system are presented to facilitate an understanding of the experiments described, but a detailed examination of the relationships of nerves and muscles or of the innervation of the latter was not attempted. The spontaneous activity of such preparations was recorded kymographically and the characteristics of this activity under 'normal' conditions are described, together with observations on the effects on the normal spontaneous activity of treatments with sea waters of different ionic composition and with a number of drugs. The responses of the preparation to controlled electrical stimulation are also reported. The results are analysed and compared with the results of similar investigations on other invertebrate preparations, in particular the Anthozoa, and an interpretation of these results in terms of platyhelminth-coelenterate relations is discussed.
- Full Text:
- Date Issued: 1961
- Authors: Boyle, Sheila A
- Date: 1961
- Subjects: Platyhelminthes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5902 , http://hdl.handle.net/10962/d1013541
- Description: From Resumé: The general picture of the physiology of invertebrate neuro-muscular systems as contrasted with the classical vertebrate system is presented and it is clear that one of the groups least investigated is the Phylum Platyhelminthes. An examination of the properties of the myo-neural system of a platyhelminth should be of interest, not only in itself, but also because of a possible relationship with the coelenterates, whose neuro-muscular system has been fairly extensively investigated. The aim of the present work was to determine some of the properties of the myo-neural system of a platyhelminth, and more especially those which would make possible a comparison with the myo-neural systems of other invertebrate phyla, and most particularly with the coelenterates. A preparation consisting of an entire decerebrate animal was used. The general anatomy of the musculature and basic plan of the nervous system are presented to facilitate an understanding of the experiments described, but a detailed examination of the relationships of nerves and muscles or of the innervation of the latter was not attempted. The spontaneous activity of such preparations was recorded kymographically and the characteristics of this activity under 'normal' conditions are described, together with observations on the effects on the normal spontaneous activity of treatments with sea waters of different ionic composition and with a number of drugs. The responses of the preparation to controlled electrical stimulation are also reported. The results are analysed and compared with the results of similar investigations on other invertebrate preparations, in particular the Anthozoa, and an interpretation of these results in terms of platyhelminth-coelenterate relations is discussed.
- Full Text:
- Date Issued: 1961
The geology of the Bindura granite complex in Southern Rhodesia
- Authors: Bowen, David James
- Date: 1961
- Subjects: Geology -- Zimbabwe -- Bindura , Granite outcrops -- Zimbabwe -- Bindura
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5073 , http://hdl.handle.net/10962/d1013529
- Description: From Introduction: The object of the investigation was to examine the variations in the granite and the relation between the granite and the surrounding metamorphosed sedimentary rocks of the Shamvaian System (Primitive). Although this object may not have been fully achieved, it has been possible to show that a wide variety of rocks is present in the area, and a few suggestions as to their origin have been made.
- Full Text:
- Date Issued: 1961
- Authors: Bowen, David James
- Date: 1961
- Subjects: Geology -- Zimbabwe -- Bindura , Granite outcrops -- Zimbabwe -- Bindura
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5073 , http://hdl.handle.net/10962/d1013529
- Description: From Introduction: The object of the investigation was to examine the variations in the granite and the relation between the granite and the surrounding metamorphosed sedimentary rocks of the Shamvaian System (Primitive). Although this object may not have been fully achieved, it has been possible to show that a wide variety of rocks is present in the area, and a few suggestions as to their origin have been made.
- Full Text:
- Date Issued: 1961
The history and the problems of Bantu urban secondary education in the Eastern Cape, 1937-1954 (Ciskei region)
- Authors: Dyasi, Hubert Mongameli
- Date: 1961
- Subjects: Black people -- Education -- South Africa -- Ciskei , Black people -- Education -- South Africa -- Eastern Cape -- History
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1997 , http://hdl.handle.net/10962/d1014827
- Description: 1. Reasons for Choosing the Topic. Much has been written about secondary education in England, Continental Europe, the United States, Canada, China and other countries mainly "because Secondary Education has been one of the most prized of all formal types of education ... because it has been the rung of the educational ladder that has led to opportunity and preferment". Very little research work has been done on Bantu secondary education in the Ciskei, and still less about Bantu urban secondary education. This is a shortcoming since the Ciskei has been one of the most important educational areas for the Bantu in the Union of South Africa and the territories outside her borders. It was here that the experiment of Bantu day secondary schools was carried out. It could aptly have been said of the Ciskei, too, that "experimental work (destined one day to blaze into a consuming fire) has been carried on, where men and women of faith and inspiration have lit up some dark corner of the field, and where teachers of genius have defied tradition and convention, gone their own way in scorn of consequence, and have lit a candle which will never be put out". The Bantu Urban Day Secondary Schools started amidst conflicting opinions as regards their advantages and disadvantages. Difficulties were encountered and efforts made to overcome them. The present writer attempts to show how the problems of these schools were overcome and to assess the progress that was made. 2. Need for the Study. There is a great need for the study of the history and problems of Bantu Urban Day Secondary education because for many years to come these schools will have to serve an increasing number of urban Bantu pupils. The results of the research may serve as a guide to teachers appointed to these schools. The important history of these institutions preserved only in the minds of old men and women, may be lost to posterity. There is also a great need to bring to light the unique problems confronting these schools. 3. Scope of Dissertation. The dissertation limits itself to Bantu Urban Day secondary education, in specific areas of the Ciskei. Two secondary and two high schools have been chosen for special study. Bantu Urban Day Secondary Schools are those schools which are situated in areas under the jurisdiction of municipalities or town councils irrespective of whether the school admits largely pupils who are outside such an area or only those within it or both. The entrance qualification to these schools has always been a pass in Standard VI (normally after eight years of primary or elementary schooling). For the Bantu pupil the Junior Certificate Course was of three years' duration. The successful completion of the J.C. course qualified pupils to train as nurses, in the case of girls, and agricultural demonstrators in the case of boys. Both sexes could undertake studies for Native Primary Higher Teachers' Course, and the Senior Certificate Course or the Matriculation leading to university degrees.
- Full Text:
- Date Issued: 1961
- Authors: Dyasi, Hubert Mongameli
- Date: 1961
- Subjects: Black people -- Education -- South Africa -- Ciskei , Black people -- Education -- South Africa -- Eastern Cape -- History
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1997 , http://hdl.handle.net/10962/d1014827
- Description: 1. Reasons for Choosing the Topic. Much has been written about secondary education in England, Continental Europe, the United States, Canada, China and other countries mainly "because Secondary Education has been one of the most prized of all formal types of education ... because it has been the rung of the educational ladder that has led to opportunity and preferment". Very little research work has been done on Bantu secondary education in the Ciskei, and still less about Bantu urban secondary education. This is a shortcoming since the Ciskei has been one of the most important educational areas for the Bantu in the Union of South Africa and the territories outside her borders. It was here that the experiment of Bantu day secondary schools was carried out. It could aptly have been said of the Ciskei, too, that "experimental work (destined one day to blaze into a consuming fire) has been carried on, where men and women of faith and inspiration have lit up some dark corner of the field, and where teachers of genius have defied tradition and convention, gone their own way in scorn of consequence, and have lit a candle which will never be put out". The Bantu Urban Day Secondary Schools started amidst conflicting opinions as regards their advantages and disadvantages. Difficulties were encountered and efforts made to overcome them. The present writer attempts to show how the problems of these schools were overcome and to assess the progress that was made. 2. Need for the Study. There is a great need for the study of the history and problems of Bantu Urban Day Secondary education because for many years to come these schools will have to serve an increasing number of urban Bantu pupils. The results of the research may serve as a guide to teachers appointed to these schools. The important history of these institutions preserved only in the minds of old men and women, may be lost to posterity. There is also a great need to bring to light the unique problems confronting these schools. 3. Scope of Dissertation. The dissertation limits itself to Bantu Urban Day secondary education, in specific areas of the Ciskei. Two secondary and two high schools have been chosen for special study. Bantu Urban Day Secondary Schools are those schools which are situated in areas under the jurisdiction of municipalities or town councils irrespective of whether the school admits largely pupils who are outside such an area or only those within it or both. The entrance qualification to these schools has always been a pass in Standard VI (normally after eight years of primary or elementary schooling). For the Bantu pupil the Junior Certificate Course was of three years' duration. The successful completion of the J.C. course qualified pupils to train as nurses, in the case of girls, and agricultural demonstrators in the case of boys. Both sexes could undertake studies for Native Primary Higher Teachers' Course, and the Senior Certificate Course or the Matriculation leading to university degrees.
- Full Text:
- Date Issued: 1961
The role of the church in an urban African society
- Authors: Dubb, Allie A
- Date: 1961
- Subjects: Bhengu, Nicholas B H, 1909- , Pentecostal churches -- South Africa -- East London
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3361 , http://hdl.handle.net/10962/d1011563 , Bhengu, Nicholas B H, 1909- , Pentecostal churches -- South Africa -- East London
- Description: This study is based on research carried out in East London, South Africa during the period September 1957 to August 1959 as an Assistant Research Officer of the Institute for Social and Economic Research, Rhodes University. The study is presented in three parts and its theme, broadly speaking, is the role of the church in an urban African society. In Part I, some aspects of the African Church in East London are discussed in general terms and an attempt was made to relate our own material with the findings of other researchers. Emerging from this discussion we have concluded that the Church could potentially play an important part in combating the social disorganization characteristic of urban locations in South Africa, but that on the whole this potential has not been fully exploited.
- Full Text:
- Date Issued: 1961
- Authors: Dubb, Allie A
- Date: 1961
- Subjects: Bhengu, Nicholas B H, 1909- , Pentecostal churches -- South Africa -- East London
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3361 , http://hdl.handle.net/10962/d1011563 , Bhengu, Nicholas B H, 1909- , Pentecostal churches -- South Africa -- East London
- Description: This study is based on research carried out in East London, South Africa during the period September 1957 to August 1959 as an Assistant Research Officer of the Institute for Social and Economic Research, Rhodes University. The study is presented in three parts and its theme, broadly speaking, is the role of the church in an urban African society. In Part I, some aspects of the African Church in East London are discussed in general terms and an attempt was made to relate our own material with the findings of other researchers. Emerging from this discussion we have concluded that the Church could potentially play an important part in combating the social disorganization characteristic of urban locations in South Africa, but that on the whole this potential has not been fully exploited.
- Full Text:
- Date Issued: 1961
A study of the fluorescence excitation spectrum of crystalline anthracene
- Authors: Driver, Adrian Stanford
- Date: 1960
- Subjects: Fluorimetry , Anthracene crystals -- Spectra
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5518 , http://hdl.handle.net/10962/d1011463 , Fluorimetry , Anthracene crystals -- Spectra
- Description: The work described in this thesis was performed at the Physics Department, Rhodes University during 1958 and 1959 under the supervision of Professor J.A. Gledhill. Use was made of a vacuum ultra-violet spectrograph which had been constructed in the Physics Department (1.1) and modifications to be described were made to this instrument. The instrument was used for studying the effects of oxygen on the fluorescence excitation spectrum of Anthracene.
- Full Text:
- Date Issued: 1960
- Authors: Driver, Adrian Stanford
- Date: 1960
- Subjects: Fluorimetry , Anthracene crystals -- Spectra
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5518 , http://hdl.handle.net/10962/d1011463 , Fluorimetry , Anthracene crystals -- Spectra
- Description: The work described in this thesis was performed at the Physics Department, Rhodes University during 1958 and 1959 under the supervision of Professor J.A. Gledhill. Use was made of a vacuum ultra-violet spectrograph which had been constructed in the Physics Department (1.1) and modifications to be described were made to this instrument. The instrument was used for studying the effects of oxygen on the fluorescence excitation spectrum of Anthracene.
- Full Text:
- Date Issued: 1960
An investigation of the profiles of bursts of solar radio noise
- Wild, Peter Anthony Thornton
- Authors: Wild, Peter Anthony Thornton
- Date: 1960
- Subjects: Solar radio emission , Radio noise , Solar noise storms , Radio astronomy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5551 , http://hdl.handle.net/10962/d1013504
- Description: [Summary] Chapter I . The general characteristics of solar radiation at metre wavelengths are described, with reference to data published in the literature. A brief description of some aspects of solar physics relevant to the study of solar noise is given, and the literature relating to the correlation of radio effects with solar disturbances is reviewed. Chapter II. A concise description of the apparatus constructed for the continuous recording of the flux density of solar radio noise at a frequency of 300 Mc/s is given, with some mention of difficulties experienced, and how these were overcome. Full circuit diagrams of electronic apparatus, and illustrative photographs, are supplied. Chapter III. The development of theories of the origin and propagation of solar noise radiation is historically reviewed and the success of each theory in explaining or predicting observed phenomena, is assessed. A working model is chosen from among these theories, and reasons for its adoption are given. Chapter IV. Observations made by the author of solar radiation at a frequency of 300 Mc/s are described, together with a description of the objects and methods, of analysis of the records. Chapter V. Phenomena observed by the author are compared with those observed by other workers. It is concluded that storm bursts are caused by transients similar to those producing Type II and Type ITI bursts, and a model for the production of storm bursts is tentatively suggested. Chapter VI. Suggestions for further research, including suggestions for methods of testing the author's conclusions, are made.
- Full Text:
- Date Issued: 1960
- Authors: Wild, Peter Anthony Thornton
- Date: 1960
- Subjects: Solar radio emission , Radio noise , Solar noise storms , Radio astronomy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5551 , http://hdl.handle.net/10962/d1013504
- Description: [Summary] Chapter I . The general characteristics of solar radiation at metre wavelengths are described, with reference to data published in the literature. A brief description of some aspects of solar physics relevant to the study of solar noise is given, and the literature relating to the correlation of radio effects with solar disturbances is reviewed. Chapter II. A concise description of the apparatus constructed for the continuous recording of the flux density of solar radio noise at a frequency of 300 Mc/s is given, with some mention of difficulties experienced, and how these were overcome. Full circuit diagrams of electronic apparatus, and illustrative photographs, are supplied. Chapter III. The development of theories of the origin and propagation of solar noise radiation is historically reviewed and the success of each theory in explaining or predicting observed phenomena, is assessed. A working model is chosen from among these theories, and reasons for its adoption are given. Chapter IV. Observations made by the author of solar radiation at a frequency of 300 Mc/s are described, together with a description of the objects and methods, of analysis of the records. Chapter V. Phenomena observed by the author are compared with those observed by other workers. It is concluded that storm bursts are caused by transients similar to those producing Type II and Type ITI bursts, and a model for the production of storm bursts is tentatively suggested. Chapter VI. Suggestions for further research, including suggestions for methods of testing the author's conclusions, are made.
- Full Text:
- Date Issued: 1960
Some aspects of the chemistry of zirconium compounds relating to their combination with collagen
- Williams-Wynn, David Ernest Arthur
- Authors: Williams-Wynn, David Ernest Arthur
- Date: 1960
- Subjects: Zirconium compounds , Collagen
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4513 , http://hdl.handle.net/10962/d1013456
- Description: [Summary] Some properties of zirconium compounds in aqueous solution have been determined using physico-chemical techniques. Zirconium oxychloride was used as the source of zirconium in all detailed investigations; zirconium sulphate was used in a few cases for comparative purposes. The Stokes diaphragm cell method has been used to determine the diffusion coefficient of zirconium in hydrochloric acid solution. It was found that the diffusion coefficient fell progressively with time, a limiting value being reached 4 to 5 weeks after dissolving the salt, and it was demonstrated that particles in the aged solutions were more homogeneous than in freshly prepared solutions. The limiting values were concentration dependent; dilute solutions had a lower diffusion coefficient than the more concentrated solutions when measured at the natural pH. In the presence of added acid the rate of diffusion was increased until a limiting value was reached in 0.5 M acid. The addition of alkali or complexing acids reduced the rate of diffusion.
- Full Text:
- Date Issued: 1960
- Authors: Williams-Wynn, David Ernest Arthur
- Date: 1960
- Subjects: Zirconium compounds , Collagen
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4513 , http://hdl.handle.net/10962/d1013456
- Description: [Summary] Some properties of zirconium compounds in aqueous solution have been determined using physico-chemical techniques. Zirconium oxychloride was used as the source of zirconium in all detailed investigations; zirconium sulphate was used in a few cases for comparative purposes. The Stokes diaphragm cell method has been used to determine the diffusion coefficient of zirconium in hydrochloric acid solution. It was found that the diffusion coefficient fell progressively with time, a limiting value being reached 4 to 5 weeks after dissolving the salt, and it was demonstrated that particles in the aged solutions were more homogeneous than in freshly prepared solutions. The limiting values were concentration dependent; dilute solutions had a lower diffusion coefficient than the more concentrated solutions when measured at the natural pH. In the presence of added acid the rate of diffusion was increased until a limiting value was reached in 0.5 M acid. The addition of alkali or complexing acids reduced the rate of diffusion.
- Full Text:
- Date Issued: 1960
The contribution of the Anglican church to education in the Cape
- Authors: Rawlins, G E
- Date: 1960
- Subjects: Church and education -- South Africa , Church of England -- Education -- South Africa , Education -- South Africa -- Cape of Good Hope
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1978 , http://hdl.handle.net/10962/d1013055
- Description: In his "Onderwys in Kaapland, 1652 - 1939", Dr. P.S. du Toit makes special references to the educational work of the Anglican Church, indicating that there is some contribution. This attitude has as its aim to expose more of the reef of which the outcrops receive attention by Dr. du Toit ... much can happen between 1807 and 1829, and some of what did is described in these pages. One of Dr. du Toit's interests is the effect of the attempt to make English and instruction in English the basis of all education. Chap. 1, p. 1.
- Full Text:
- Date Issued: 1960
- Authors: Rawlins, G E
- Date: 1960
- Subjects: Church and education -- South Africa , Church of England -- Education -- South Africa , Education -- South Africa -- Cape of Good Hope
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1978 , http://hdl.handle.net/10962/d1013055
- Description: In his "Onderwys in Kaapland, 1652 - 1939", Dr. P.S. du Toit makes special references to the educational work of the Anglican Church, indicating that there is some contribution. This attitude has as its aim to expose more of the reef of which the outcrops receive attention by Dr. du Toit ... much can happen between 1807 and 1829, and some of what did is described in these pages. One of Dr. du Toit's interests is the effect of the attempt to make English and instruction in English the basis of all education. Chap. 1, p. 1.
- Full Text:
- Date Issued: 1960
The diary of C. L. Stretch - a critical edition and appraisal
- Authors: Crankshaw, Grahame Bruce
- Date: 1960
- Subjects: Stretch, Charles Lennox, 1797-1882 , South Africa -- History -- Frontier Wars, 1811-1878 , Treaties -- Interpretation and construction
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2535 , http://hdl.handle.net/10962/d1002387 , Stretch, Charles Lennox, 1797-1882 , South Africa -- History -- Frontier Wars, 1811-1878 , Treaties -- Interpretation and construction
- Description: In the investigation of the Diary and its validity as evidence, the origin and structure of the treaty System, and the functioning of the treaties, in both their original form and subsequent modification, has been examined, with special reference to Stretch and the Gaika tribes.
- Full Text:
- Date Issued: 1960
- Authors: Crankshaw, Grahame Bruce
- Date: 1960
- Subjects: Stretch, Charles Lennox, 1797-1882 , South Africa -- History -- Frontier Wars, 1811-1878 , Treaties -- Interpretation and construction
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2535 , http://hdl.handle.net/10962/d1002387 , Stretch, Charles Lennox, 1797-1882 , South Africa -- History -- Frontier Wars, 1811-1878 , Treaties -- Interpretation and construction
- Description: In the investigation of the Diary and its validity as evidence, the origin and structure of the treaty System, and the functioning of the treaties, in both their original form and subsequent modification, has been examined, with special reference to Stretch and the Gaika tribes.
- Full Text:
- Date Issued: 1960
The thermal decomposition of silver oxide
- Authors: Herley, Patrick James
- Date: 1960
- Subjects: Silver oxide -- Thermal properties , Decomposition (Chemistry)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4525 , http://hdl.handle.net/10962/d1015017
- Description: [From Introduction]. The thermal decomposition of solids is characterized by the formation and growth of nuclei at sites on the surface of the solid or within the crystal lattice. Such nuclear formation is favoured by disorganisation of the crystal either by mechanical damage, or by the presence of impurities. Disorganisation results in positions which have a high thermodynamic instability. The nuclei are likely to be formed initially at the corners and the edges of the crystal since these are more prone to damage. Careful handling and storage in vacuo often leads to a large reduction in their number, while deliberate scratching of the surface facilitates their production. The number of potential sites for nuclear formation is also increased by pre-irradiation with ultra-violet light, though there are indications that a different type of nucleus may be produced. Nucleation can be facilitated by pre-irradiation with electrons, neutrons, X-rays, gamma-rays and atomic particles. The nature of the nuclei is not always clearly defined, but it is generally accepted that they are composed of solid reaction products e.g. in the decomposition of barium azide and silver oxalate, nuclei of metallic barium and silver, respectively, are formed.
- Full Text:
- Date Issued: 1960
- Authors: Herley, Patrick James
- Date: 1960
- Subjects: Silver oxide -- Thermal properties , Decomposition (Chemistry)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4525 , http://hdl.handle.net/10962/d1015017
- Description: [From Introduction]. The thermal decomposition of solids is characterized by the formation and growth of nuclei at sites on the surface of the solid or within the crystal lattice. Such nuclear formation is favoured by disorganisation of the crystal either by mechanical damage, or by the presence of impurities. Disorganisation results in positions which have a high thermodynamic instability. The nuclei are likely to be formed initially at the corners and the edges of the crystal since these are more prone to damage. Careful handling and storage in vacuo often leads to a large reduction in their number, while deliberate scratching of the surface facilitates their production. The number of potential sites for nuclear formation is also increased by pre-irradiation with ultra-violet light, though there are indications that a different type of nucleus may be produced. Nucleation can be facilitated by pre-irradiation with electrons, neutrons, X-rays, gamma-rays and atomic particles. The nature of the nuclei is not always clearly defined, but it is generally accepted that they are composed of solid reaction products e.g. in the decomposition of barium azide and silver oxalate, nuclei of metallic barium and silver, respectively, are formed.
- Full Text:
- Date Issued: 1960
A quantitative investigation of the absorption of certain cations by whole plants and plant tissues
- Cresswell, Christopher Frederick
- Authors: Cresswell, Christopher Frederick
- Date: 1959 , 2014-07-24
- Subjects: Cations -- Absorption and adsorption , Plant tissues
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4262 , http://hdl.handle.net/10962/d1013335
- Description: Introduction: Part 1. Greenhouse studies were conducted to investigate the absorption of sodium, potassium, calcium and magnesium by lemon seedlings. The plants were grown in controlled nutrient solutions and analysis of the plant material was made to determine the relationship between the four cations in the different plant organs. Results of the experiment may be summarized as follows:- The occurrence of leaf burn appeared to be associated with a low calcium content, together with a high sodium, potassium or sodium + potassium content. The development of the seedlings was shown to be markedly influenced by the level of calcium supply and to a much lesser degree by the level of potassium supplied. The concentration of sodium, potassium, calcium and magnesium in the stem and leaf varied with position of the tissues on the main axis. The level of sodium was found to influence the distribution of sodium in the leaves, and the sodium content of the leaf, stem and root tissues gave a good reflection of the level of sodium supplied. The effect of the sodium treatment on the uptake of potassium appeared to be dependent on the calcium content of the tissues. Sodium treatment was found not to affect the leaf calcium content. In the stem and root tissues the calcium content was reduced when the calcium level in the nutrient medium was low, and increased the calcium content of these two tissues at the higher level of calcium supply. The sodium supply was shown to reduce the leaf magnesium only slightly, and its affect on the magnesium content of the stem and root tissues was shown to be dependent on the level of calcium supplied. The potassium content of the leaves, stems and roots increased when the supply of potassium was raised. Increasing the potassium level in the nutrient supply was found to cause a very slight reduction in the sodium content of the leaf, but did not affect the sodium content of the stem and root. Potassium did not affect the calcium content of the leaves and increased the stem calcium when sodium was not present in the nutrient media in high concentrations. In the roots potassium only increase the calcium content at the upper level of calcium supply. The magnesium content of the leaf and stem tissues was reduced as the potassium supply was increased. In the roots the general trend was for the magnesium content to increase when the level of potassium treatment was raised. The calcium content of all the plant parts increased with a rise in the calcium supply, the stem and root tissues having a greater percentage increase than the leaves. The sodium content of the plant tissue was reduced as the level of calcium supply was raised. The leaf potassium content decreased with a higher calcium level of supply. In the stem and roots the potassium content was increased by doubling the calcium supply. The calcium treatment had no influence on the magnesium content of the foliage, but in the stem and root tissues a decrease in magnesium content resulted from an increase in the calcium supply. Part II Potato tuber tissue and carrot root tissue were used as experimental material in the investigation of sodium9 potassium9 and calcium uptake by storage tissue. It was shown that when the tissue disks are transferred from distilled water to a solution of salts there is a rapid initial uptake of cation which is neither particularly selective, nor related to metabolism, but dependent on the external concentration. On the other hand, the prolonged active accumulation of cation exhibits selectivity. Potassium absorption by potato tuber tissue was shown to be stimulated by sodium9 whereas the potassium and calcium absorption by carrot root tissue was shown to be reduced by sodium. Similarly the sodium absorption by the carrot root tissue was reduced by potassium, thus suggesting that the cations compete with one another for the same absorption mechanism.
- Full Text:
- Date Issued: 1959
- Authors: Cresswell, Christopher Frederick
- Date: 1959 , 2014-07-24
- Subjects: Cations -- Absorption and adsorption , Plant tissues
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4262 , http://hdl.handle.net/10962/d1013335
- Description: Introduction: Part 1. Greenhouse studies were conducted to investigate the absorption of sodium, potassium, calcium and magnesium by lemon seedlings. The plants were grown in controlled nutrient solutions and analysis of the plant material was made to determine the relationship between the four cations in the different plant organs. Results of the experiment may be summarized as follows:- The occurrence of leaf burn appeared to be associated with a low calcium content, together with a high sodium, potassium or sodium + potassium content. The development of the seedlings was shown to be markedly influenced by the level of calcium supply and to a much lesser degree by the level of potassium supplied. The concentration of sodium, potassium, calcium and magnesium in the stem and leaf varied with position of the tissues on the main axis. The level of sodium was found to influence the distribution of sodium in the leaves, and the sodium content of the leaf, stem and root tissues gave a good reflection of the level of sodium supplied. The effect of the sodium treatment on the uptake of potassium appeared to be dependent on the calcium content of the tissues. Sodium treatment was found not to affect the leaf calcium content. In the stem and root tissues the calcium content was reduced when the calcium level in the nutrient medium was low, and increased the calcium content of these two tissues at the higher level of calcium supply. The sodium supply was shown to reduce the leaf magnesium only slightly, and its affect on the magnesium content of the stem and root tissues was shown to be dependent on the level of calcium supplied. The potassium content of the leaves, stems and roots increased when the supply of potassium was raised. Increasing the potassium level in the nutrient supply was found to cause a very slight reduction in the sodium content of the leaf, but did not affect the sodium content of the stem and root. Potassium did not affect the calcium content of the leaves and increased the stem calcium when sodium was not present in the nutrient media in high concentrations. In the roots potassium only increase the calcium content at the upper level of calcium supply. The magnesium content of the leaf and stem tissues was reduced as the potassium supply was increased. In the roots the general trend was for the magnesium content to increase when the level of potassium treatment was raised. The calcium content of all the plant parts increased with a rise in the calcium supply, the stem and root tissues having a greater percentage increase than the leaves. The sodium content of the plant tissue was reduced as the level of calcium supply was raised. The leaf potassium content decreased with a higher calcium level of supply. In the stem and roots the potassium content was increased by doubling the calcium supply. The calcium treatment had no influence on the magnesium content of the foliage, but in the stem and root tissues a decrease in magnesium content resulted from an increase in the calcium supply. Part II Potato tuber tissue and carrot root tissue were used as experimental material in the investigation of sodium9 potassium9 and calcium uptake by storage tissue. It was shown that when the tissue disks are transferred from distilled water to a solution of salts there is a rapid initial uptake of cation which is neither particularly selective, nor related to metabolism, but dependent on the external concentration. On the other hand, the prolonged active accumulation of cation exhibits selectivity. Potassium absorption by potato tuber tissue was shown to be stimulated by sodium9 whereas the potassium and calcium absorption by carrot root tissue was shown to be reduced by sodium. Similarly the sodium absorption by the carrot root tissue was reduced by potassium, thus suggesting that the cations compete with one another for the same absorption mechanism.
- Full Text:
- Date Issued: 1959
A study of the biology of the Jameson reservoir near Grahamstown, Cape Province
- Authors: Darbyshire, John Frederick
- Date: 1959
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/6784 , vital:21179
- Description: 1. This thesis is an ecological study of a South African water storage reservoir and it’s tributary streams. 2. A brief description of the reservoir, the surrounding vegetation, superficial geological strata, soils and early history of the reservoir is given in Chapter I. 3. The surrounding vegetation is discussed in some detail in Chapter II. The zonation of the plants and the influence of water upon it are discussed. 4. The results of the regular investigations of the physicochemical environment are presented in Appendix 1 and the salient points noted in Chapter III. 5. The species of algae collected are listed in Appendix 2 and in Chapter IV are discussed in relation to habitat and abundance. 6. The animals are dealt with in a similar manner in Chapter V. Under 'Discussion and Conclusions' in Chapter VI an attempt is made to review the findings and discuss their significance.
- Full Text:
- Date Issued: 1959
- Authors: Darbyshire, John Frederick
- Date: 1959
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/6784 , vital:21179
- Description: 1. This thesis is an ecological study of a South African water storage reservoir and it’s tributary streams. 2. A brief description of the reservoir, the surrounding vegetation, superficial geological strata, soils and early history of the reservoir is given in Chapter I. 3. The surrounding vegetation is discussed in some detail in Chapter II. The zonation of the plants and the influence of water upon it are discussed. 4. The results of the regular investigations of the physicochemical environment are presented in Appendix 1 and the salient points noted in Chapter III. 5. The species of algae collected are listed in Appendix 2 and in Chapter IV are discussed in relation to habitat and abundance. 6. The animals are dealt with in a similar manner in Chapter V. Under 'Discussion and Conclusions' in Chapter VI an attempt is made to review the findings and discuss their significance.
- Full Text:
- Date Issued: 1959
A study of the heroine in certain Victorian novels
- Authors: Addecott, Grahame John
- Date: 1959
- Subjects: English fiction -- 19th century -- History and criticism , Heroines in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2319 , http://hdl.handle.net/10962/d1013374
- Description: During the reign of Queen Victoria was seen the gradual emergence of the emancipated woman. The idea that women were innocent beings who must be kept from real knowledge of the world died hard, however, and to the end of the era there were many who repudiated the very concept of emancipation whether in literature or life. Coupled with the chivalrous, idealistic concept of womanhood was Victorian respectability, and it is not surprising that in the earlier Victorian novels we see clearly the idealistic concept of women and the effects of the cult of respectability. To illustrate my theme, of the gradual change in the concept of the novel which naturally kept pace, more or less, with the progress the emancipation of women was making, I have chosen one novel from each of seven great Victorian novelists whose works span the whale era. The only exception I have made is with Charlotte Bronte. In her case the heroines of two of her novels are discussed mainly because she is the first Victorian novelist to sound a note of protest against the then conventional concept of the heroine.
- Full Text:
- Date Issued: 1959
- Authors: Addecott, Grahame John
- Date: 1959
- Subjects: English fiction -- 19th century -- History and criticism , Heroines in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2319 , http://hdl.handle.net/10962/d1013374
- Description: During the reign of Queen Victoria was seen the gradual emergence of the emancipated woman. The idea that women were innocent beings who must be kept from real knowledge of the world died hard, however, and to the end of the era there were many who repudiated the very concept of emancipation whether in literature or life. Coupled with the chivalrous, idealistic concept of womanhood was Victorian respectability, and it is not surprising that in the earlier Victorian novels we see clearly the idealistic concept of women and the effects of the cult of respectability. To illustrate my theme, of the gradual change in the concept of the novel which naturally kept pace, more or less, with the progress the emancipation of women was making, I have chosen one novel from each of seven great Victorian novelists whose works span the whale era. The only exception I have made is with Charlotte Bronte. In her case the heroines of two of her novels are discussed mainly because she is the first Victorian novelist to sound a note of protest against the then conventional concept of the heroine.
- Full Text:
- Date Issued: 1959
A study of the predators and parasites of Planococcus citri (Risso) (Homoptera) on vines in the Western Cape Province, South Africa
- Authors: Whitehead, Vincent Booth
- Date: 1959
- Subjects: Hemiptera , Parasites , Insect pests -- Biological control , Grapes -- Diseases and pests
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5896 , http://hdl.handle.net/10962/d1013425
- Description: [Introduction] In the Western Cape Province the mealybug, Planococcus citri (Risso), was first reported on vines in 1930 by Joubert (1943a). By 1935 this mealybug had spread to the Hex River Valley, and subsequently to all the main table grape producing areas of the Western Cape Province. At present Pl. citri is the most important insect pest of the table grape industry and can, if not effectively controlled, result in a loss of at least five per cent of the export table grape crop (Kriegler, 1954). Some preliminary work on the natural enemies of Pl. citri on vines was carried out by Stubbings in 1948, but no further work of this nature has been undertaken in this area since then. The fact that the natural enemies can be an effective check to this mealybug on vines in the Western Cape Province has been known for a number of years (Potgieter, 1937; Hattingh, 1943; Joubert, 1943a; Myburgh, 1951). The present work is an attempt to obtain some basic knowlege of the population fluctuations of the insects concerned in this biological control. Surveys undertaken have shown that there is a complex of primary, secondary and possibly tertiary Hynenopterous parasites associated with Pl. citri. The presence of hyperparasites reduces the efficiency of the primary parasitic Hymenoptera. The usefulness of these primary parasites is further reduced as they only occur in effective numbers for a short period of the year. On the other hand, although attacked by some parasites, the numerous coccinellids found preying on Pl. citri are of more importance in reducing the mealybug populations, as they are present on the vines in effective numbers for the greater part of the year.
- Full Text:
- Date Issued: 1959
- Authors: Whitehead, Vincent Booth
- Date: 1959
- Subjects: Hemiptera , Parasites , Insect pests -- Biological control , Grapes -- Diseases and pests
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5896 , http://hdl.handle.net/10962/d1013425
- Description: [Introduction] In the Western Cape Province the mealybug, Planococcus citri (Risso), was first reported on vines in 1930 by Joubert (1943a). By 1935 this mealybug had spread to the Hex River Valley, and subsequently to all the main table grape producing areas of the Western Cape Province. At present Pl. citri is the most important insect pest of the table grape industry and can, if not effectively controlled, result in a loss of at least five per cent of the export table grape crop (Kriegler, 1954). Some preliminary work on the natural enemies of Pl. citri on vines was carried out by Stubbings in 1948, but no further work of this nature has been undertaken in this area since then. The fact that the natural enemies can be an effective check to this mealybug on vines in the Western Cape Province has been known for a number of years (Potgieter, 1937; Hattingh, 1943; Joubert, 1943a; Myburgh, 1951). The present work is an attempt to obtain some basic knowlege of the population fluctuations of the insects concerned in this biological control. Surveys undertaken have shown that there is a complex of primary, secondary and possibly tertiary Hynenopterous parasites associated with Pl. citri. The presence of hyperparasites reduces the efficiency of the primary parasitic Hymenoptera. The usefulness of these primary parasites is further reduced as they only occur in effective numbers for a short period of the year. On the other hand, although attacked by some parasites, the numerous coccinellids found preying on Pl. citri are of more importance in reducing the mealybug populations, as they are present on the vines in effective numbers for the greater part of the year.
- Full Text:
- Date Issued: 1959
A study of the relationship between the poetry and criticism of Ezra Pound 1908-1920
- De Villiers, André Rex Wepener
- Authors: De Villiers, André Rex Wepener
- Date: 1959
- Subjects: Pound, Ezra, 1885-1972 -- Criticism and interpretation
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2317 , http://hdl.handle.net/10962/d1013320
- Description: From the preface: The purpose of this thesis is exposition rather than criticism. Pound's position in the hierarchy of the 'New Criticism' would provide an extremely interesting subject; but I have rather tried to outline; the standards which he has laid down as being central in the technics of good poetry and to show how closely he has adhered to them in his own verse. I have limited the period to be discussed because all of the essential principles which he employs in his writing after 1920 are discernible in the body of his work published before that date.
- Full Text:
- Date Issued: 1959
- Authors: De Villiers, André Rex Wepener
- Date: 1959
- Subjects: Pound, Ezra, 1885-1972 -- Criticism and interpretation
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2317 , http://hdl.handle.net/10962/d1013320
- Description: From the preface: The purpose of this thesis is exposition rather than criticism. Pound's position in the hierarchy of the 'New Criticism' would provide an extremely interesting subject; but I have rather tried to outline; the standards which he has laid down as being central in the technics of good poetry and to show how closely he has adhered to them in his own verse. I have limited the period to be discussed because all of the essential principles which he employs in his writing after 1920 are discernible in the body of his work published before that date.
- Full Text:
- Date Issued: 1959
The economic geography of the Union's chicory Industry : past and present
- Authors: Young, Bruce Stratton
- Date: 1959
- Subjects: Chicory -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:4882 , http://hdl.handle.net/10962/d1013438
- Description: The motivating force behind this survey and study of a branch of the Union's agricultural industry has been the conviction that detailed case studies of economic activities and their influences on the map of the country are the essential foundation stones on which mature scholars may build a perceptive and valuable economic geography of the Union.
- Full Text:
- Date Issued: 1959
- Authors: Young, Bruce Stratton
- Date: 1959
- Subjects: Chicory -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:4882 , http://hdl.handle.net/10962/d1013438
- Description: The motivating force behind this survey and study of a branch of the Union's agricultural industry has been the conviction that detailed case studies of economic activities and their influences on the map of the country are the essential foundation stones on which mature scholars may build a perceptive and valuable economic geography of the Union.
- Full Text:
- Date Issued: 1959