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An investigation of the behaviour and biology of the Citrus Mussel Scale, Lepidosaphes Beckii (Newm.)

- Hulley, Patrick Elliot

  • 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.
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  • Date Issued: 1961

An investigation of the polarization of solar radio noise

- Verschuur, Gerrit L.,1937-

  • 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.
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  • Date Issued: 1961

Chocolates for my wife [corrected author's version]

- Matshikiza, Todd

  • Authors: Matshikiza, Todd
  • Date: 1961
  • Subjects: Matshikiza, Todd, 1921-1968 , Musicians, Black -- Biography , Matshikiza Family
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/39873 , vital:24930 , This manuscript is held at the Cory Library for Humanities Research at Rhodes University. For further information contact cory@ru.ac.za. The digitisation of this image was made possible through a generous grant received from the Andrew W. Mellon Foundation 2014-2017. , MS 20 068
  • Description: Description on the back of published version (published in 1982 by Africasouth Paperbacks by David Philip): "Of Chocolates for my wife, first published in 1961 (and 'banned' in South Africa until July 1982), Matshikiza said, "This is a book about real people, many of them my friends, and about a few of the experiences I have share with them." It tells in his own wry, vivacious, coruscating style of black life in the Johannesburg of Orlando, Sophiatown and Alexandra Township when King Kong was in rehearsal - and in sharp contrast to this, of the adventures of the Matshikiza family in London." This book was first published by Hodder & Stoughton, London in 1961.
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  • Date Issued: 1961

Construction of a wide-frequency range double heterodyne conductance bridge and its use in the investigation of polarisation errors in conductance measurements

- Govinden, Herby Silvester

  • Authors: Govinden, Herby Silvester
  • Date: 1961
  • Subjects: Electrodynamics Electrolytes -- Conductivity
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5522 , http://hdl.handle.net/10962/d1012074
  • Description: (1) Developments in a.c. conductance techniques during the past ninety years have been reviewed, and a brief outline is given of the older theories regarding electrolytic polarisation. (2) A conductance bridge - incorporating the double heterodyne principle - has been constructed, capable of giving resistance readings to an accuracy of 0.01% over a range of frequencies covering the best part of 100 kc/s. It has also been found possible to calibrate the oscillator so that frequency settings can be guaranteed to an accuracy of , at least, 0.1% in the range: 2 kc/S to 50 kc/S. (3) The Wheatstone Bridge Network has been slightly modified to enable measurements at the high frequencies. (4) Resistances in the measuring arm of the bridge have been calibrated 'in situ' by the method of intercomparison. (5) A brief description is given of the modern theories regarding electrode processes and modern methods of eliminating electrode effects. (6) Two types of conductance cells, with bright Pt electrodes, have been used to carry out measurements on potassium chloride solutions: (a) Thomas- Gledhill Cell (b) Nichol-Fuoss Cell. The latter incorporates concentric, cylindrical electrodes with the lead to the outer electrode acting as an electrical shield for the lead to the inner electrode. This cell was constructed and used for the first time in this laboratory. (7) From resistance-frequency graphs plotted, it is shown that the Jones and Christian extrapolation procedure cannot be applied (with any degree of confidence) to obtain the true resistance, when measurements are effected over an extended range of frequencies. (8) The method of resistance-reactance diagrams is discussed and applied to various networks of resistances and capacitances. (9) By drawing resistance-reactance diagrams for the experimental readings obtained, equivalent circuits have been derived - for all the solutions investigated in the N-F cell, and for the approx. O.OlD solution in the T-G cell - which approximate to cell behaviour in the range: 500 c/s to 75 kc/s. The less concentrated solutions in the T-G cell show peculiar behaviour at the high frequencies. (10) Probable reasons are advanced for deviations from linearity on resistance-frequency graphs. (11) A new method is proposed for determining the true resistance of solutions measured in cells of the N-F type. Summary, p. 166-167.
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  • Date Issued: 1961

Fishes of the family Anthiidae

- Smith, J.L.B. (James Leonard Brierley), 1897-1968

  • Authors: Smith, J.L.B. (James Leonard Brierley), 1897-1968
  • Date: 1961
  • Subjects: Ground beetles , Fishes -- Classification , Fishes -- Indian Ocean , Fishes -- Red Sea
  • Language: English
  • Type: Text
  • Identifier: vital:14984 , http://hdl.handle.net/10962/d1018951 , Ichthyological Bulletin; No. 21
  • Description: These fishes are generally assigned to the family Serranidae, one of the most diverse and cumbersome groups of fishes. Containing numerous ill-assorted types this family for convenience at least merits sub-division. One of the natural sub-groups, generally given sub-family status as the Anthiinae, but here given full family rank, consists mainly of small, brilliant, free-swimming coral haunting types confined almost exclusively to tropical seas. These d iffer from the Serranidae proper in the absence of a supramaxilla, in having larger scales, in the dentition, and mostly in the concave or lunate caudal. Although by most workers assigned without question to the Serranidae (sensustricto) the monotypic genus Variola Swainson, 1839 has distinct affinities with the Anthiidae. The dentition, lunate caudal and the brilliant colouration accord better with the Anthiid than with the Serranid fishes. , Rhodes University Libraries (Digitisation)
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  • Date Issued: 1961

Fishes of the family Apogonidae of the Western Indian Ocean and the Red Sea

- Smith, J.L.B. (James Leonard Brierley), 1897-1968

  • Authors: Smith, J.L.B. (James Leonard Brierley), 1897-1968
  • Date: 1961
  • Subjects: Cardinalfishes , Fishes -- Classification , Fishes -- Indian Ocean , Fishes -- Red Sea
  • Language: English
  • Type: Text
  • Identifier: vital:14985 , http://hdl.handle.net/10962/d1018952 , Ichthyological Bulletin; No. 22
  • Description: Fishes of the family Apogonidae of the Western Indian Ocean and the Red Sea. Small and relatively feeble as most of these fishes are many cover an astonishing range. Some are found over truly vast areas of the Indo-Pacific, ranging from Southern Africa to the mid-Pacific. As a result, workers on even mid-Pacific Apogonidae need to give heed to the fauna of the Red Sea and of the Western Indian Ocean, from where, as in the case of the Parrot fishes, many early types were described. Failure to do this has caused species from the Pacific described as new, later to be proved identical with those long known from the Red Sea or the Indian Ocean. , Rhodes University Libraries (Digitisation)
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  • Date Issued: 1961

Fishes of the family Xenopoclinidae

- Smith, J.L.B. (James Leonard Brierley), 1897-1968

  • Authors: Smith, J.L.B. (James Leonard Brierley), 1897-1968
  • Date: 1961
  • Subjects: Clinidae
  • Language: English
  • Type: Text
  • Identifier: vital:14982 , http://hdl.handle.net/10962/d1018781 , Ichthyological Bulletin; No. 20
  • Description: As is w ell know n, there is a sharp line of distinction at the Cape between the warmer waters of the east and south coast of Africa, and the cool seas of the western Cape areas, with corresponding cleavage in the marine fauna. It was in this cooler area that a specimen of the first member of this group, Xenopoclinus kochi Smith, 1947, was discovered, and at that time it was given subfamily rank in the Clinidae. Until recently only the holotype was known, but now not only have further specimens been secured, but also a second species in this genus, and even more striking is the discovery of a second genus and a third species from the same locality. These forms all show clear relationship with the Blennioid fishes, but despite the numerous families in that order, I cannot find any among them that are so clearly related to the fishes described here, as to be able to assign this small group with certainty to anyone. The peculiar characters appear to merit full family rank, as is given here. , Rhodes University Libraries (Digitisation)
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  • Date Issued: 1961

Gold fineness in hydrothermal ores : an investigation into the distribution of gold and silver in Southern Rhodesian gold ores

- Eales, Hugh V

  • Authors: Eales, Hugh V
  • Date: 1961
  • Subjects: Hydrothermal deposits -- Zimbabwe , Gold ores -- Zimbabwe , Silver ores -- Zimbabwe , Silver mines and mining -- Zimbabwe
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5077 , http://hdl.handle.net/10962/d1014887
  • Description: This investigation is concerned with primary variations in the silver content of gold which occurs in hydrothermal deposits, particularly those of hypothermal character which are found in Basement rocks in Southern Rhodesia. The nature of the gold produced by a number of different mines has been studied by reference to production data, and microscope techniques as well as gold and silver assays have been used to determine and to explain the variations in gold fineness. The literature does not contain a great deal of information which is relevant to this topic, but an attempt has been made here to summarize the more important contributions by different writers. From this it emerges that the interpretations given by different investigators are in conflict and that paradoxes may arise when efforts are made to explain observed variations in fineness in terms of certain generalizations which have become entrenched in the literaure. In particular, it is shown that falling temperature alone cannot account for the occurrence of silver-rich gold in certain deposits. The Gwanda district of Southern Rhodesia has been selected as a typical gold belt, and the variation in fineness in 150 producers is described. The deposits are hypothermal in character, and the average fineness of the gold is high but variable, but in a small proportion the fineness is low. It is shown that the nature of the host rock and the distance of a deposit from the granite contact appear to have no influence on the fineness of the gold and that there is no zonal arrangement of fineness values. There is a suggestion that diversity of mineral species in any particular area may be accompanied by rather wide fluctuations in the gold fineness. The variations of fineness in eight typical Southern Rhodesian deposits are studied in detail, by analysis of production data, by assaying specimens of the ore and by the examination of polished specimens of gold-bearing ore. Briefer reference is made to two other deposits in the territory, and to deposits in other countries which appear to bear out the conclusions reached in this section. It emerges that there are two factors which can commonly be correlated with variations in fineness. The first of these is the grade of the ore: high-grade ore generally contains purer gold than low-grade ore. Secondly, the textural evidence indicates that gold which separates relatively early in the paragenesis contains more silver than that which is deposited in the final stages of metallization. A general survey which draws on the literature as well as on the writer's examinations of deposits in the territory indicates that, in general, gold which is associated with late-stage minerals such as tellurides, antimony, bismuth and bismuthinite is silver-poor. Gold associated with galena may be either silver-rich or silver-poor, whereas gold which is of the same age as chalcopyrite or sphalerite is very frequently rich in silver. The difficulty which is encountered in establishing the age of gold which is intimately associated with pyrite and arsenopyrite renders uncertain the correlation between fineness and age of gold in these latter cases. There are, however, indications that gold which is truly contemporaneous with either pyrite or arsenopyrite is silver-rich. In the discussion, the objections to the common practice of singling out temperature as the most potent factor controlling gold fineness are listed. Chief amongst these objections is the fact that gold does not in all deposits increase in fineness with increasing depth: examples are quoted where fineness was found to decrease as deeper levels of the ore body were exploited. It is shown that there is no consistent relationship between the size of gold grains and their silver content. It is the writer's conclusion that in hydrothermal deposits in this territory the high fineness of the gold is due to increasing solubility of silver in the ore fluids in the late states, and that where hydrothermal deposits are characterized by gold with low average fineness, an unusually large proportion of the gold has been deposited early in the paragenotic sequence. In the majority of hypothermal deposits, however, the bulk of tho gold separates late in the sequence and the fineness is accordingly high. It is believed that the relationship which exists between fineness and tenor in many deposits is due to protracted crystallization of gold in those portions of the ore body which remained permeable to the latest stages. These portions of the ore body, which represent either valuable ore shoots or ore shoots in miniature, are likely to contain gold of variable character, but the average silver content will be low because a large proportion of the gold is "late" gold. The factors which might cause epithermal gold to have a lower fineness than mesothermal or hypothermal gold are briefly discussed. Some possible applications of this study are indicated in the final chapter. It is claimed that records of gold fineness might constitute a valuable addition to mill records. Tentative suggestions are made regarding a method whereby the approaching exhaustion of a deposit might in some cases be predicted. With regard to the origin of the gold in the Witwatersrand sediments, it is pointed out that the modified placer hypothesis is not fully equipped to explain certain of the variations in the composition of the gold.
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  • Date Issued: 1961

Investigation of the formation of complexes between selected organic compounds and the chlorides and sulphates of chromium

- Ellis, Melville John

  • 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.
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  • Date Issued: 1961

John X. Merriman : the making of a South African statesman (1869-1878)

- Gruber, R F J

  • 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.
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  • Date Issued: 1961

Letter from P.C. Kruger

- Kruger, P C

Lucan, poet of freedom : inaugural lecture delivered at Rhodes University

- Dilke, Oswald Ashton Wentworth

Pineapples in the Eastern Cape : a study of the farm economy and marketing patterns

- Strauss, Conrad B

  • Authors: Strauss, Conrad B
  • Date: 1961
  • Subjects: Pineapple industry -- South Africa -- Eastern Cape , Agriculture -- Economic aspects -- South Africa , Farm produce -- Marketing
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:1103 , http://hdl.handle.net/10962/d1013318
  • Description: The major objective of this study was to seek a better knowledge and greater understanding of the factors associated with successful pineapple farming in the Eastern Cape Region of the Union of South Africa. As no previous · investigation equally representative of commercial pineapple farming patterns in the Eastern Cape has been made, this study can be regarded as a pilot survey of the labour structures, rates of production, combination of enterprises; marketing channels and the suitability of various districts in the region of study for the production of pineapples. In addition, the history of the pineapple in South Africa will be traced briefly, and the position the Union holds as a supplier of pineapples on the world market, will be investigated. the importance of the Eastern Cape as a producer of pineapples in South Africa is well known, but is also unequivocally illustrated by the information in Table 1. According to estimates made by the Division of Economics and Markets for 1955/56 season, no less than 86.5 percent of the total acreage planted to pineapples in South Africa, was located in this area. Bathurst, East London and Albany, three of the six districts included in the estimate, were particularly prominent. Taken together, they cultivated more than three-quarters of the total area planted to pineapples in the Eastern Cape, and nearly 70 per cent of the total for South Africa. The remaining quarter of the area cultivated in the Eastern Cape was located in the districts of Peddie, Komgha and Alexandria.
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  • Date Issued: 1961

Rhodes University Graduation Ceremony 1961

- Rhodes University

  • Authors: Rhodes University
  • Date: 1961
  • Language: English
  • Type: text
  • Identifier: vital:8095 , http://hdl.handle.net/10962/d1004410
  • Description: Rhodes University Graduation Ceremonies in the University Great Hall on Saturday , 8th April, 1961, at 11 a.m. [and] Saturday , 22nd April, 1961, at 11 a.m.
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  • Date Issued: 1961

South African Coloured National Convention, Claremont Civic Centre, 7th to 10th July 1961

- Convention Central Office

South African Coloured National Convention. National Continuation Committee. Annexure "A" to the minutes of 7th 1961 meeting

- South African National Coloured Convention

Studies on the neuro-physiology of a free-living Platyhelminth

- Boyle, Sheila A

  • 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.
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  • Date Issued: 1961

The border region : a geographical study of land utilization

- Board, Christopher

The culture plan : world techniques in uniformity : inaugural lecture delivered at Rhodes University

- Bradshaw, Brian

  • Authors: Bradshaw, Brian
  • Date: 1961
  • Subjects: Culture
  • Language: English
  • Type: Text
  • Identifier: vital:604 , http://hdl.handle.net/10962/d1020673
  • Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
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  • Date Issued: 1961

The geology of the Bindura granite complex in Southern Rhodesia

- Bowen, David James

  • 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.
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  • Date Issued: 1961
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