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Q. 22. Describe the principal species of Mica which occur as rock

constituents, indicating the particular class of rocks in which

each of these species occurs. Most of the candidates are acquainted with the chief characters of Muscovite and Biotite, but do not recognize the existence of any other kinds of Mica. Instead of stating the class of rocks in which the several species of Mica occur, they give a list of names of micaceous rocks. Q. 23. State the mineralogical constitution and the structure of common

basalt, and indicate the relations to basalt of the following rocks :a) Tachylyte ; () Gabbro ; (c) Variolite ; (d) Amygda

loidal Melaphyre. This question, which is selected by a considerable majority of the candidates, is, on the whole, very well answered. Among the mineral constituents of Basalt, olivine, magnetite and glass are frequently omitted. Very few appear to be acquainted with Variolite, and the nature and mode of origin of Amygdaloids is not well understood. Q. 24. Give an account of the nature and origin of (a) Slickensides,

(6) Crushed and impressed pebbles, (c) Friction Breccias, (d)

Mylonites. Also answered by a majority of the candidates. A considerable amount of knowledge is shown concerning Slickensides and Friction Breccias ; but the statements about Crushed and Impressed Pebbles are evidently guesses, based on the name and its association, while little knowledge is shown concerning Mylonites. Q. 25. Describe the composition and modes of occurrence of Septaria,

and explain their origin. This question, which is selected by only a few of the candidates, is by no means so well answered as might have been anticipated. Q. 26. Draw a section showing beds of limestone and slate traversed by

reversed step-faults and overlain by false-bedded sands. Selected by nearly all the candidates, and fairly good drawings are given. In some cases, however, the diagram is incomplete, the most prevalent error being a failure to make clear the unconformable relations. of the false-bedded sands to the faulted strata below. Q. 27. Give an account of the nature and origin of different varieties of

Volcanic Bombs. What are Pseudo-volcanic Bombs, and how

are they formed ? That this subject is still imperfectly taught is shown by the circumstance that very few of the candidates attempted an answer to the question. Of this small number scarcely any show any real knowledge concerning the nature and origin of Volcanic Bombs and the objects which simulate them. Q. 28. Describe the composition, structure and relations of the rock

called Troctolite (“Forellenstein"). The half a dozen candidates who alone selected this question give good answers to it-some of them excellent ones.

But it is evident that practical petrological teaching at this advanced stage is not as good as could be desired. Q. 29. Describe the relations of the Coal Measures in the Midland

Coalfields of England to the strata which lie above and below

them respectively. This question when selected is not very satisfactorily answered. Many of the candidates appear to think that a general statement of the carboniferous succession is all that is required. At present there does not seem to be much geological teaching with an economic bearing. Q. 30. Give an account of the nature and mode of formation of the

chief deposits of iron-ore which are of economic importance. It is evident that the teaching had not covered the subject of this question. The answers are few and very imperfect in almost all cases,

Q. 31. Describe, with the aid of sketches, the jointing of limestone rocks

and explain how the operation of quarrying is facilitated by the

presence of joints. The subject of joints had clearly been well taught and as a rule their economic value and importance are recognised. The one point upon which there is some ambiguity is the necessity of bedding planes as well as of two sets of joint planes for the quarrying of cuboidal blocks.


STAGE 3. Results: 1st Class, 18; 2nd Class, 13; Failed, 9; Total, 40. In this stage there is not only a marked increase in the number of candidates, but a very considerable improvement is manifested in the character of the answers. Many of the descriptions given of the Radiolarian Ooze are very full and complete, the most serious error (which is only seen in a few cases) is the failure to recognize the siliceous character of the skeletons of Radiolaria. It is a strange circumstance that some among the candidates, who give fair descriptions of the Radiolarian Cherts, argue that the occurrence of these among upraised stratified rocks must be regarded as an evidence in favour of the permanence of Ocean-basins. In connection with Question 42, it is a very gratifying circumstance to find that some of the candidates have evidently visited the dry valleys of Yorkshire and Derbyshire, while one of them has evidently made a personal examination of the Mole Valley. The accounts given of the appearances witnessed in these valleys, and of the methods of experimenting with a view to determine the actual courses of the underground streams, are in every way admirable. It is not apparent from the papers whether these geological excursions had been made under the guidance and direction of the teacher, or had been undertaken by the students upon their own initiative. In the Question on Coral Reefs (43) a good deal of ignorance was shown concerning the important part played by Calcareous Algæ ("Nullipores”), Foraminifera, and other organisms in forming reefs. This, however, is probably due to the imperfect accounts given in most of the text-books. `Neither in the answers to Question 44 (Spherulites and Lithophyses), nor in that to Question 46 Peridotites), is a very satisfactory knowledge of Petrology shown. Probably few of the schools are provided with the microscopes and specimens necessary for teaching the subject practically. Side by side with several very weak answers to Question 45 (on a comparison of the Faunas of the Crag and Glacial periods), there were two or three very full and complete ones, showing much knowledge and intelligence on the part of the candidates. On the whole, we consider the results in this stage to compare very favourably with those of last year. They afford evidence of excellent and, we think we may add, enthusiastic teaching, and the way in which out-of-door work has been undertaken is most praiseworthy.

Honours. Results : 1st Class, 5 ; 2nd Class, 6 ; Failed, 1 ; Total, 12. There is the same number of Honours papers in Geology this year as there was in 1905 ; but the Failures are fewer and the First Classes more numerous. There is a very considerable improvement in the quality of the answers, especially to the Palæontological questions. It was an unfortunate circumstance that one of the candidates, who had to be placed in the Second Class, after giving excellent answers to three questions, stated that he was unable to attempt a fourth for want of time. His failure to complete the paper was undoubtedly owing to the undue amount of time which he had devoted to the three questions answered. There is evidence in nearly all the papers sent in of much careful reading and study, and the papers certainly reach the highest University standard. The greatest weakness is shown in the subjects of Petrology and Stratigraphical Geology. The want of success in Petrology is probably due to insufficient equipment of the schools. The weakness in Stratigraphical Geology is less easily accounted for, seeing that provision was made for students residing in different areas by giving a choice for description of a Palæozoic, a Mesozoic and a Cainozoic formation. It is surprising to find that few candidates appear to be aware of the fact that Garnets, of several species, form important constituents of some igneous, as well as of many metamorphic rocks.

Report on the Examination in Mineralogy.

There is an increase in the number of papers as compared with 1905. The teaching still seems to be excellent in this subject, the percentage of failures being still very low, though there is a decline in the number obtaining a First Class. The only ground of regret is that the subject is not more generally taught, especially in the mining districts.

STAGE 1. Results : 1st Class, 19; 2nd Class, 24; Failed, 5; Total, 48. In the increased number of papers in this stage there are very few failures, but the number of First Classes is not quite as high as was the case last year. The great increase is in the number who obtained a Second. Class. Q. 1. Draw (a) an Octahedron, (b) a Rbomb-dodecahedron, (c) a com

bination of these two forms. Name a common mineral which

is found crystallised in each of these forms. Of the rather more than half the candidates who attempted this question, the great majority find no difficulty in drawing the Octahedron and the Rhomb-dodecahedron. But a considerable number experience difficulty in representing a combination. Without an opportunity of handling models of crystals, it is to be feared that such difficulty will always be felt. Q. 2. Name (a) a mineral which exhibits Adamantine lustre, (6) one

showing, Vitreous lustre, (c) one with Metallic lustre, (d) one with Submetallic lustre, (e) one with Earthy lustre. State

what is meant by (f) Dichroism, and (9) Trichroism. Good answers are the rule as far as the first part of the question is concerned, and good selections are made of minerals exhibiting different varieties of lustre. Dichroism and Trichroism are, however, seldom well understood, confusion with particolour, play of colours, and even dimorphism being frequent. Q. 3. Give the names of the minerals which exhibit magnetic properties,

and state how you would test the magnetism of a mineral. This question is only moderately well answered, and very few of the candidates recoguise the existence of “polarity” in magnetic minerals. Q. 4. Calcite and Aragonite are said to be “dimorphous forms of the

same chemical compound.” Explain what is meant by this

statement. Most of the candidates appear to understand the term “ dimorphism." The difference of crystal form is generally recognised, though often badly expressed, but the difference in other physical properties of Calcite and Aragonite are seldom referred to. Q. 5. Describe the minerals which are sulphides of iron, lead and zinc,

respectively. Well answered except in certain cases, where neither Marcasite nor Pyrrhotite are enumerated among the iron-sulphides.

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Q. 6. What is a Pseudomorph? Describe three commonly occurring

pseudomorphs, stating how each has been formed. This question was not so frequently attempted as the last, but those who selected it appear to have understood what pseudomorphism really is, difficulties in definition appearing to be due rather to want of powers of expression, than to want of knowledge of the subject. Q. 7. What is the crystalline form of Native Sulphur? How and where

has this mineral been formed. Selected by very few candidates. Some of these give excellent answers, but others rather indifferent ones. Q. 8. From what sources is the metal Tin obtained ? State the modes of

occurrence of tin-ores. More than half the candidates attempted this question, and the answers are uniformly good. Q. 9. What are the chief minerals which occur as “ veinstones” in

association with ores? Give the chemical composition of each

of these veinstones. Among the few candidates who selected this question there is a strange want of clear perception of the difference between“ veinstones” and “ Q. 10. Name the three specimens placed before you ; give the chemical

composition of each, and the system in which it crystallises. Also make a qualitative blowpipe-analysis of each of the two powdered minerals supplied to you. State your results clearly ; if any chemical symbols or abbreviations are used, write them

distinctly. Of the minerals given, Actinolite (Hornblende) is seldom recognised. Selenite is generally rightly named and described, and the candidates are equally successful with the Stibnite. The blowpipe work is fairly well done. In the powdered Barium Carbonate, Calcium and Strontium are often found, and the Barium is sometimes missed. Nearly all determine the Cuprite.


Stage 2.


Results : 1st Class, 6 ; 2nd Class, 16 ; Failed, 2 ; Total, 24. In this stage the number of candidates is rather less than last year, but the number of failures is equally small. The proportion of First to Second Class is this year rather lower than in 1905. On the whole, the results may be regarded as very satisfactory, there being good evidence of careful teaching. Q. 21. Draw a commonly occurring crystal of Augite, indicating the

forms present in it. How do crystals of Augite and Hornblende

generally differ from one another ? Selected by one-third of the candidates, all of whom, with two or three exceptions, give good and correct answers. Q. 22. What are the chief precautions necessary in taking the specific

gravity of a crystal or cut gem by means of a chemical balance ? Also attempted by one-third of the candidates, who give intelligent and fairly good answers. Q. 23. Describe exactly what is seen when a section cut from a crystal

of Hornblende is rotated in a polariscope or polarising micro

scope, (a) over a single Nicol prism, (6) between crossed Nicols. The same proportion of the candidates selected this as attempted the two previous questions. The great defect in the answers is a failure to recognise the distinctive appearances when the crystal sections are cut in different directions. It is to be feared that few of the candidates have an opportunity of seeing these appearances for themselves.

Q. 24. In what respects do crystals of Orthoclase, Microcline, and

Oligoclase resemble one another, and in what respects do they

differ? This question was attempted by a much smaller number of candidates. The answers are correct, but unnecessarily verbose. Instead of confining themselves to definite points of resemblance and difference, the candidates write long descriptions of the three minerals. Q. 25. Describe the three models placed before you, giving a sketch

of each to show which axis you place in an upright position.

In each case name a mineral that crystallises in the form shown. Although the answers to this question are generally correct, there is one very prevalent error, namely, in the position of the axes in the Tristetrahedron. This mistake is probably due to trusting to drawings instead of handling models of the crystals. Q. 26. Name the three specimens placed before you ; give the chemical

composition of each, and the system in which it crystallises. Also make a qualitative blowpipe-analysis of each of the two powdered minerals supplied to you. Tabulate the results, stating, how each was obtained ; if any chemical symbols or

abbreviations are used, write them distinctly. This question was only moderately well answered. Of the minerals for determination Zincite is almost always correctly identified, Molybdenite is frequently mistaken for Graphite, while no candidate correctly identified Brucite. The blowpipe-work is much better done, the elements present both in Cobaltite and Pyrohisite being found, though the inferences drawn are sometimes less satisfactory. Q. 27. Describe the mineral Nepheline-its crystalline form, chemical

composition, and physical properties -stating the chief rocks

in which it occurs as an Essential Constituent. About one-fourth of the candidates who attempted this question answer it very well. Q. 28. Give an account of the Sodium, Potassium, and Ammonium

Chlorides occurring as minerals, describing the mode of occurrence

and origin of each. One half of the candidates selected this question, and give good answers, except with respect to the origin and mode of occurrence of Ammonium Chloride-a subject which does not appear to have been properly taught. Q. 29. Describe the Oxides of Iron (both anhydrous and hydrous) which

are used for the extraction of iron. Well answered in nearly all cases, full and complete accounts of the several minerals being given. Q. 30. Give an account of the mineral Talc, its composition and

properties, the forms which it assumes, and the uses to which it is put. Point out the difference between the commercial and

scientific uses of the term "talc.” Very few candidates attempted this question ; only one of them is aware of the difference between the commercial and the scientific use of the term "talc”; and, generally, the uses of the mineral are entirely ignored.

Q. 31. Describe the chief minerals which constitute ores of Silver.

This was the question in the Technical Series which was most often selected, and it is extremely well answered. Q. 32. What is known concerning the nature and origin of Jet, Amber,

and Emery! Why are these substances no longer regarded as

minerals? One fourth of the candidates attempted this question, but many of them appear to be vague in their ideas concerning the modern definition of

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