400 



SCIENTIFIC NEV\AS. 



[April 27, iS 



in the second portion, of all the principal testing and 

 recording instruments, carefully and excellentlj'illustrated, 

 now in use in the chief engineering laboratories ; and we 

 can heartily congratulate Professor Unwin on the com- 

 pleteness and care with which it is evident this volume 

 has been produced. It will undoubtedly take a prominent 

 place among the standard works on constructive en- 

 gineering. 



Elementary Chemistry, Inorganic and Organic. Adapted 

 to the Requirements of the " Alternative Elementary 

 Syllabus" of the Scienc'- and Art Department. By 

 W. S. Furneaux, F.R.G.S , Science Demonstrator, 

 London School Board. London : Longmans,' Green 

 and Co. 

 Works like the one before us are apt to suggest certain 

 difficult questions. How is it, for instance, that so many 

 elementary chemical treatises appear differing from each 

 other little, if at all, as far as the subject matter is con- 

 cerned ? What can be the raison d'etre of three-fourths 

 of them ? How is it that they can alwajs find pub- 

 lishers ? How is it that, unlike German manuals of 

 chemistry or of any other science, they are, with few excep- 

 tions, "adapted" to some examination or "sylla- 

 bus " ? 



Mr. Furneaux hopes that his work may be a useful 

 introduction to the study of othersciences, many of the 

 facts and principles of which cannot be properly grasped 

 \yj a mind totally ignorant of chemistry. He avoids, as 

 far as possible, technical language. He informs the 

 pupil how to perform certain experiments, for the most 

 part very simple, and shows him what inferences are to 

 be drawn from the results. 



In speaking of the atmosphere, he makes, of course 

 inadvertently, a strange inversion. We read that nitro- 

 gen " forms one-fifth of air and supports combustion," 

 whilst oxygen " forms four-fifths of the air and does not 

 support combustion." There are other passages in the 

 book from which the true properties of these gases 

 appear, but we fear that the statement quoted may 

 perplex beginners. 



In proof of the proposition that when a substance 

 burns it increases in weight, we find directed an experi- 

 ment which does not seem judicious. Says the author : — 

 " Balance some iron-powder (ferriim vidactum should be 

 reductitm) on a pan of a delicate pair of scales, and cause 

 it to burn by applying heat. As the iron burns it com- 

 bines with oxj'gen of the air, and the increase in the 

 weight ot the pan will be proved by the falling of the 

 pan containing it." The application of heat to any sub- 

 stance in the pan of a " delicate " balance, and that, more- 

 over, whilst the pan is still in suspension, seems a 

 hazardous and unwise proceeding. Experienced chemists 

 never place any substance on the pan of the balance 

 until it has been cooled down to the temperature of the 

 air. 



In speaking of the substances obtained from coal, Mr. 

 Furneaux writes : — " The beautiful aniline colours are 

 produced by the distillation of tar." This is surely an 

 unhappy way of explaining the origin of the coal-tar 

 colours. Mere distillation, even if fractionated, would 

 never yield these dyes. There are a few other errors 

 and some repetitions, but in general we may say that 

 the book will be useful for those who wish to acquire 

 an elementary knowledge of chemistrj'. In how far it 

 may suit students " preparing for examinations " we are 

 unable to say. 



Transactions of the Manchester Geological Society. Vol. 

 xix., Parts 16 and 17. 



In the former of these numbers we find " Observa- 

 tions on Boulders from the High Level Drift of Bacup," 

 by Mr. Herbert Bolton. The boulders in question are 

 of volcanic origin, apparently derived from the English 

 Lake District. Indeed, a closer examination has enabled 

 the author to identifj' these boulders with rocks in the 

 localities from which they have been carried. He con- 

 siders that three well-defined beds of glacial drift may 

 be traced in the Bacup area. 



Reference was made to the views of Mr. Carrill Lewis, 

 who had found at Bacup the moraine of a great glacier, 

 which chocked up the Irish Sea, and which may be 

 traced through Bacup, Hey, Stalybridge, Stockoort, and 

 Macclesfield, being as finely developed as the moraines 

 of Switzerland and America. He considers that at 

 Manchester the ice was at least 1,400 feet thick. Pro- 

 fessor Boyd Dawkens controverted the views of Mr. 

 Carrill Lewis as not in harmony with facts. 



Two papers on " Boulders in Coal Seams " were 

 communicated by Mr. Cowburn and Mr. Sterrup, to 

 which we hope to refer elsewhere. 



In No. 17 is noticed a short paper of Mr. C. Handwick 

 on the " Granite of the Mullett, Ireland," illustrated by 

 specimens and by a picture of the rocks taken by Mr. 

 Robert Pollitt. 



Journal of the Society of Telegraph Engineers and 

 Electr.cians. Vol. xvii., No. 71. 

 This issue comprises a very important paper by Mr. 

 Gisbert Kagog on " Alternate Current Transformers, 

 with special reference to the best proportion between 

 Iron and Copper." Concerning the distribution of 

 electric energy to consumers, the speaker remarked 

 that of the three methods in practical use, " our own is 

 the worst, the American slightly better, and the Con- 

 tinental the best." "To string high-tension wires over 

 and across our streets, allow high tension branch-leads 

 to pass into our houses, and give every subscriber a 

 little transformer to himself, more or less within the 

 reach of the inmates, seems to me to be positively 

 courting disaster." Also a paper read by Mr. J. 

 Kenneth Mackenzie on the "Distribution of Electricity 

 by means of Secondary Generators or Transformers," 

 and Mr. Gisbert Kagog gave an abstract of a communica- 

 tion by Prof. G. Forbes, entitled " Formulas for Con- 

 verters." 



— «-j>;^^5*5-» — 



EXAMINERS AND CANDIDATES. 



IT has been the writer's fortune to sit at several 

 examinations, and to set a good many examina- 

 tion papers. Perhaps some hints of what he has learned 

 by experience may interest the very numerous people 

 who belong either to the class of examiners or to that of 

 candidates. 



Smce the ways of the examiner govern the ways of 

 the candidate, it will be best to look at the subject, in the 

 first place, from the examiner's point of view. It is 

 generally an easy and not unpleasant business to set the 

 paper. The exercise of devising questions which give a 

 new air to familiar facts, and the power of directing a 

 good many men's thoughts for some few hours at least in 

 a channel of his own, is a gentle stimulus to the 

 examiner's mind. He does not realise for a good while 

 how difficult it is to be just to all parties, and when he 



