124 



NATURE 



[June 8, 1882 



or fractions of things. Much useful, if elementary, infor- 

 mation is conveyed in small doses as the child is able to 

 receive it, but there is nothing childish in the matter or 

 the manner. We should say that the best way to use the 

 book would be for the parent (or governess) to master 

 each lesson well beforehand, so that there should be little 

 or no reference to the book during lesson-time, except, 

 perhaps, for the purpose of looking at the illustrative 

 drawings. We feel sure that when the "good bye" is 

 reached there will be few to call Arithmos unkind names 

 and say "he is a horrid, cross old thing," and that "they 

 hate him, and wish such a giant had never been made." 



A Treatise on Elementary Trigonometry. By the Rev. 



J. B. Lock. (Macmillan, 1882.) 

 Introduction to Plane Trigonometry. By the Rev. T. 



G. Vyvyan. (Deighton, Bell, and Co., 1882.) 

 Both these works are elementary : their scope is in the 

 main limited by the requirements of the Previous Exam- 

 ination at Cambridge, and of the Entrance Examinations 

 for the army. Mr. Lock's is by far the fuller work, and 

 is well adapted for a student who has not constantly at 

 hand the assistance of a private tutor ; in fact, such a 

 reader, if of fair intelligence, might be independent of 

 extraneous aid, if he have previously grounded himself 

 carefully in geometry and elementary algebra. The work 

 contains a very large collection of good (and not too hard) 

 examples. The only fault — if we must grumble — is that 

 there is too much, we think, for ordinary school teaching. 

 As Mr. Vyvyan remarks. " in all public schools but a few 

 hours a week can be given to mathematics by the gene- 

 rality of boys," and trigonometry has to take, in general, 

 a very small portion of that limited time. But Mr. Lock 

 is to be congratulated, when so many " Trigonometries " 

 are in the field, on having produced so good a book, for 

 he has not merely availed himself of the labours of his 

 predecessors, but by his treatment of a well-worn subject 

 has invested the study of it with interest. The figures 

 are numerous, and are drawn so that the salient features 

 arrest the eye at once. 



Mr. Yyvyan's work also is well adapted to the end he 

 has in view. He aims at producing a book which may 

 fairly be mastered by any schoolboy of average ability, 

 whose sole desire in studying this branch (or any other 

 branch of mathematics) is to satisfy the University ex- 

 aminers in an early stage of residence, that so he may 

 be free to read other subjects, and bid farewell to 

 mathematics. 



The matter is clearly, though somewhat concisely put, 

 and is sufficient in quantity for Mr. Vyvyan's purpose, 

 which is not to bring out a book that will render a school- 

 boy or other junior student independent of the assistance of 

 a master — this he considers to be an impossible task. We 

 ourselves have found that very much explanation is re- 

 quired by the generality of pupils. There is a sufficient 

 collection and variety of exercises. 



Wc cannot say that cither text-book will supersede all 

 other text-books, but each merits, and will no doubt 

 secure a very fair circulation in schools. Mr. Lock's 

 being the fuller, is likely to be the more generally 

 acceptable. 



An Elementary Treatise on Conic Sections. By Charles 



Smith, M.A. (London : Macmillan, 1882.) 

 A THOROUGHLY excellent elementary treatise. For a 

 long time we have been exercised in mind when asked to 

 recommend a book on Conies. To all its predecessors, 

 with their varying shades of goodness and badness, we 

 had some objection or other to urge. Mr. Smith has just 

 met our want ; his book is right up to the time, and is 

 admirably adapted for the preparation of pupils for college 

 scholarships ; for students at the university it is a fitting 

 introduction to that as yet unapproached work, Salmon's 

 treatise on these curves. The text is excellent, full in 



alternative proofs, and suggestive in its methods ; the 

 numerous worked-out exercises, in addition to those col- 

 lected at the close of the several chapters, render the 

 reader independent of any other work. We think the 

 title-page should state that it is an "analytical" treatise 

 on conies. 



LETTERS TO THE EDITOR 



[The Editor dots not hold himself responsible for opinions expressid 

 by his correspondents. Neither can he undertake to return, 

 or to correspond with the writers of, rejected manuscripts. 

 No notice is taken of anonymous communications. 



[ The Editor urgently requests correspondents to keep their letters 

 as short as possible. The pressure on his space is so great 

 that it is impossible otherwise to ensure the appearance even 

 of communications containing interesting and novel pacts.] 



The Darwin Memorial 



The note in Nature, vol. xxvi. p. 87, on the Darwin 

 memorial, >ays that there is to be a fund associated with the 

 name of the great naturalist, which shall be devoted to the 

 furtherance of biological science. Probably most biologies 

 would agree that one of the best plans for effecting this object 

 would be one, the idea of which originated with Mr. Sydney 

 1 1 icka n, of Downing College, Cambridge, who is at present on 

 the staff of the Oxford Biological Laboratory. This plan is to 

 establish out of the fund a marine zoological station somewhere 

 on the English coast, that of Devonshire, for example. Mr. 

 Hickson has advocated this course in a letter to the Times, 

 where he pointed out that Paly, Austria, and France have 

 zoo] igical Nations, while we have none, a fact which is one of 

 the many signs that the teachings of Darwin have aroused more 

 enthusiasm and activity abroad than at home. If you would 

 give publicity to this suggestion it would lie certain to come 

 under the notice of the Memorial Committee and of biologists 

 generally, J. T. Cunningham 



Cottons, Romford, May 27 



Comet a 1882 



Owing to recent bad weather, the only opportunity we have 

 had here of observing the spectrum of the comet was on June 4. 



Unfortunately our view was obstructed by clouds just as it 

 grew dusk, but a' 1 1.30 I managed to obtain a glimpse for a few 

 moments. The nucleus gave a very bright continuous spectrum, 

 with a marked increase of luminosity and widening of the spec- 

 trum in the yellow. I could see no lines or bands. I was not 

 able to make any further observations, as the comet was on the 

 point of disap) earing behind a tree. A. Percy Smith 



Temple Observatory, Rugby, June 6 



Tins comet was distinctly visible to the naked eye, at 11 p.m. 

 on Sunday, June 4, in the north-west, about 5 to io° above the 

 horizon (being in a hilly country, 1 c uld not estimate it cor- 

 rectly), with a bright nucleus, and a tail about lj° in length. 

 had been overcast and stormy all day, but cleared up 

 before midnight. I observed it from a hill-side about 400 feet 

 above sea-level. F. T. Mott 



Leicester 



Meteors 



Absence from home on business connected with the Transit 

 of Venus Expeditions prevented me sending you earlier notice of 

 a very brilliant meteor, which was seen here and at several 

 distant stations. 



On May 4, at ah. 31m. p.m., Mr. Rooney, one of the assistants 

 1 thi Observatory, saw a large fire-ball o'f a light purple tint. 

 It was first observed near the star Arcturus, and then it moved 

 towards the Great Bear, passing between S and e Ursa:. It 

 under a Ursa?, when its train changed in colour from 

 a purple tint into a brilliant red. It was visible for about five 

 seconds, and lit up the whole garden. 



Another assistant, Mr. Cullen, saw the same body from a 

 place not far distant, and his account agreed well with the above. 



A note from a friend at Clitheroe informs me that the meteor 

 was seen in that town by several persons, and was as brilliant as 

 the full moon. 



