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STAGE 3. Results : 1st Class, 11 ; 2nd Class, 155; Failed, 413 ; Total, 579. The qualitative analysis was fair on the whole, but not so good as might be expected in this stage, the majority of the candidates receiving only from 30 to 40 marks out of the 75 allotted to this part of the work. The chief mistakes may be grouped under the following heads :
(a) Arsenic acid often recorded as phosphoric acid, being missed in group ii., and noticed on the application of the molybdate test.
(6) In not a few cases phosphates were not looked for in group iii., and calcium and zinc consequently escaped recognition.
(c) The phosphate separation was in many cases not carried out properly, with the result that calcium phosphate was recorded as alumina.
(d) With five exceptions the valency of the iron and arsenic was not investigated.
The quantitative work was for the most part quite inaccurate, the percentage of carbon dioxide being usually returned 20 or 30 per cent. too high. The estimation of copper gravimetrically was almost invariably 5 or more per cent. too high. This was due to the use of caustic soda or potash as a precipitant, thus contaminating the cupric oxide with iron and with carbonate of calcium, both of which were present in the mineral. Those candidates who precipitated and weighed the copper as sulphide got fairly good results.
JULY 4TH, 1906.
10 A.M. to 5 P.M. The solution given contains one salt. Identify it and estimate
by two methods the amount present per litre of solution. The solutions given to alternate candidates contained 50 grams per litre of phosphite or hyposulphite of sodium.
One only succeeded in identifying the salt, and his estimations were not only wide of the mark, but did not agree together.
JULY 5TH, 1906.
10 A.M. to 5 P.M.
The solution given contains the chloride of tin together with a small quantity of iron.
Estimate the amount of stannous chloride present and the
total amount of tin per litre. Most of the candidates estimated the total tin with fair accuracy, but the amount of stannous chloride was usually 10 to 20 per cent. wrong.
JULY 6TH, 1906.
10 A.M. to 5 P.M.
From the salt supplied prepare the corresponding organic base. If solid, recrystallise it and determine the melting point; if liquid, distil and determine the boiling point.
Prepare a crystallised specimen of one derivative, not a salt.
Determine whether this is a primary, secondary, or tertiary base, and make some experiments with the object of discovering its constitution.
Diphenylamine and benzidine sulphates were given to alternate candidates. The work was generally very unsatisfactory. The best of the candidates got a clean crystallised specimen of the base and determined its melting point; one or two ascertained the character of the base as primary or secondary, but the specimens of derivatives handed in were not what they professed to be. One candidate was unable to commence work, not knowing how to proceed, another obtained salicylic acid from the material supplied, and a third discovered that it was tannin and proceeded to make gallic acid from it ! In these and several other cases the candidates should not have been admitted to the examination, as they had confessedly received no proper preparation in practical organic chemistry.
Eight out of fourteen candidates failed, the remaining six being placed in the second class.
ORGANIC CHEMISTRY, THEORETICAL.
Results : 1st Class, 39 ; 2nd Class, 136 ; Failed, 86 ; Tota., 261. The papers represented approximately the standard of former years. Q. 10 relating to fermentation was answered in the least satisfactory manner, after making due allowance for the fact that the subject is difficult, and any approach to a complete answer was not to be expected at this stage.
Results : 1st Class, 46; 2nd Class, 107 ; Failed, 98 ; Total, 251. On the whole the papers were good. The only question which calls for remark is No. 32, relating to alizarin, which was attempted by few, and only in one or two cases with much success.
Results : 1st Class, 1 ; 2nd Class, 23 ; Failed, 11 ; Total, 35.
ORGANIC CHEMISTRY, PRACTICAL.
Results : 1st Class, 76 ; 2nd Class, 50 ; Failed, 39 ; Total 165.
In the practical work the second exercise was not well done. As a rule the candidates, in spite of the precise instructions to the contrary given in the question, devoted all their efforts to identifying the substance by means of colour reactions, and paid little or no attention to ascertaining its chief characters.
STAGE 3. Results : 1st Class, 30; 2nd Class, 20; Failed, 21 ; Total, 71. The practical work was very poor. The preparation of the silver salt was carried out successfully, so far as could be judged from the written accounts (often very brief), but the preparation for analysis did not seem to be understood. The salt was drained on a tile, or on filter paper, or in a desiccator or on a water bath, and analysed in a wet state, as some of the candidates even pointed out! Four candidates out of thirty-five alone had the good sense to dry the salt in a steam oven until the weight was constant before proceeding to decompose it by heat.
It is difficult to imagine how students could have reached this stage without being instructed in such elementary matters.
INORGANIC CHEMISTRY, THEORETICAL.
Results : 1st Class, 235 ; 2nd Class, 127; Failed, 65 ; Total, 427. Though many of the answers were childish in style, indicating the youth of the candidates, the papers were on the whole creditable, and the diagrams were much better than those of the Evening Students. The work represents an improvement on the results of last year.
Results : 1st Class, 93 ; 2nd Class, 334 ; Failed, 253; Total, 680. There were a few excellent papers, but the majority were very weak, and many wholly unfit to present themselves in Stage 2.
It is remarkable what a large number of students persist in the belief that steam is decomposed by red hot copper, and how many introduced this idea into their answers to Q. 1 about the method of determining the composition of water by weight. There is also rather more evidence than usual of pure cram. The preparation of marsh gas for example is represented by many as resulting from “the action of caustic soda on sodium acetate," or even “by adding excess of caustic soda to acetic acid,” the statement being accompanied by a picture of a glass flask with thistle funnel and delivery tube, and with a correct equation, showing that the method has never been seen in operation, but has been learned simply from a book.
INORGANIC CHEMISTRY, PRACTICAL.
STAGE 1. Results : 1st Class, 100; 2nd Class, 55; Failed, 42; Total, 197. The results are similar to those of last year. The answers to Exercise B show that many of these students have learned to weigh with tolerable
accuracy, but in Exercise A they do not show that their powers of observa. tion have been much cultivated, for the majority of the candidates who were supplied with pure sulphur found impurity which was not present.
In connection with Exercise C the results were very poor. Nearly all the candidates used a form of apparatus in which a volume of water supposed to be equal to the volume of gas produced was syphoned off and measured. The varied and usually erroneous results obtainable with this form of apparatus in the hands of careless experimenters are well illustrated by the answers of one set of 28 candidates who all used it. Of these, two obtained approximately the correct amount of gas, three rather too little, and the remainder from two to five times the correct a mount.
STAGE 2. Results: 1st Class, 90 ; 2nd Class, 226; Failed, 88 ; Total, 404. Notwithstanding that a large proportion of the candidates secure marks sufficient for a pass, the work is not well done.
In spite of the precise instructions given by the Examiners, only about half the candidates made a separate examination of the soluble and insoluble constituents of the mixture." Zinc in Mixture II. was missed by about 90 per cent. of the candidates, while a very large number found chlorine in Mixtures I. and II. This was often traced to the common mistake of the thoughtless worker, which consists in dissolving the substance in hydrochloric acid and then testing for a chloride.
In the quantitative exercise the most common mistake was in the identification of the gas, which was nitrogen. Nearly half the candidates reported it to be ammonia, notwithstanding that they used an apparatus for collecting it filled with water.
The equations to be found in the written paper were often ludicrous, and there is too much uncertainty about the formulæ of common things, especially salts of silver.
Report on the Examinations in Metallurgy.
STAGE 1. Results : 1st Class, 48; 2nd Class, 55; Failed, 42 ; Total, 145. The standard of attainment in this stage is similar to that of last year. It is, however, encouraging to observe that the gradual improvement exhibited during recent years continues to be maintained, there being but few really worthless papers among the failures.
In making sketches, the candidates generally showed great weakness ; not only was the execution poor, but often the parts of furnaces were confused and drawn entirely in wrong proportions.
Another point to which the attention of the teachers in a few schools is called, is the failure of their students to grasp the fact that metallurgical processes are not identical with assay methods, but are concerned with materials in large quantities, and under conditions in which cost is the controlling factor. Hence, for example, sodium carbonate, however useful it is in assaying operations, would be precluded from use in a blast furnace on account of its cost alone.
The attention of teachers is again called to the reprehensible practice followed by a large number of candidates of selecting the questions they attempt to answer from ctia I. and II. only. Specialising at this early stage can inly result in an imperfect and unsatisfactory knowledge of
elementary metallurgy, and cannot be too strongly condemned. Even to those who propose entering into, or are already engaged in, iron and steel works, it is essential that they should have an acquaintance with the metallurgy of the other metals.
The remarks which follow on the answers to individual questions are confined to those only which call for special comment.
SECTION I. Q. 2. Explain the terms “ welding" and "annealing” as applied to
metals, and “dressing” as applied to ores. Give an example of
each of these operations. Many good answers, but in too many cases the term “dressing,” even when correctly explained, did not appear to be understood, the examples given of the process being quite wrong. The simple crushing of gold ores in a stamp battery was often cited as an example, as was the case last year, no reference being made to the subsequent operations which constitute the real dressing of the ore. Q. 3. What flux or fluxes would you use respectively when smelting :
(a) an ore with a siliceous gangue, (6) one with a calcareous gangue in a blast furnace, in order to obtain a fusible slag?
State your reasons for using these fluxes. Fairly well answered as a rule. The advantages of the use of two fluxes in increasing the fusibility of slags in each case were known to only one or two candidates. Q. 4. State the principles on which the manufacture of coke from coal
depends. Describe the working of a charge of coal in any oven
known to you. There were too many weak answers to this simple question. The principles were generally very imperfectly stated, and the descriptions of the working of a charge were poor, and if carried out in practice would result in the combustion and not the coking of the coal.
SECTION II. Q. 6. Give an account of the composition and general characters of the
chief iron ores. Why cannot Cleveland iron ore be used for the
production of Bessemer pig iron ? Not generally attempted. Great ignorance was displayed of the compositions and characters of the ores found in this country. Clayband ore seemed to be almost unknown, and only one candidate correctly explained why Cleveland ore was unsuitable for the production of Bessemer pig iron. Q. 7. Describe and make a sketch of a basic open hearth furnace. Give
a a description of the lining. Only a few good answers, the sketches being as a rule very poor, and representing text-book forms of old furnaces.
SECTION III. Q. 9. Name the chief re-agents in use at works for the precipitation of
gold from its solutions. Give the reactions which take place in
each case. Very few answers and all poor. Q. 10. Describe and make a sketch of a modern hand-worked reverberatory
furnace for the chloridising roasting of silver ores. Only eighteen answers, and eleven failed to obtain any marks. Only one candidate had a satisfactory knowledge of the form and construction of this simple furnace. By some candidates the furnace was drawn with a concave bed and a tap-hole, showing that they were quite ignorant of the