340 



NATURE 



{Feb. 7, 1889 



in getting his students to understand in a satisfactory way 

 the effects of changes of temperature and pressure upon 

 gases individually and in general, after the student has 

 performed the ordinary elementary experiments upon 

 the principal gases. But turning to this subject in the 

 present hand-book, we find that the student has to study 

 these effects before he has seen or read of any gas 

 whatever, unless we suppose that " the gas " at gas- 

 works, or the air mentioned in earlier chapters, will be 

 retained in the student's mind and applied by him to the 

 rules given. In the questions set on this part of the sub- 

 ject, " a gas " is the vague expression almost always 

 used, for fear, we presume, it should be imagined that the 

 rules given are more intimately connected with oxygen 

 than with hydrogen, &c. 



In the early pages the learner is introducd to gases by 

 the statement that gas-holders are "employed at gas- 

 works for holding the gas," and is then instructed, without 

 even the suggestion of an experiment, how to collect 

 gases over water and in other ways, how to transfer 

 gases to the lecture table, how to burn substances in 

 gases, to burn gases themselves, to generate gases when 

 heat is required and when heat is not required, and so 

 on. The student, having got this abstract information in 

 all its minuteness of practical detail, is expected to keep 

 it in his memory, and to work and study through nearly 

 two hundred pages dealing fully with, to him, a vast 

 variety of complex subjects, before he can apply it to 

 practical use in relation to hydrogen. By dint of much 

 searching (for there is no index, and hydrogen does not 

 appear to be mentioned at all in the meagre contents 

 table) we have found a paragraph headed "Hydrogen" 

 at p. 213. In this page no experiments are set down to 

 be done, and the first suggestion of any practical exercise 

 is the statement that " it can be obtained, as has been 

 shown (Experiment 400), by electrolyzing water." The 

 past and future are here confused, for Experiment 400 is 

 twenty-two pages further on. - This is apparently an 

 unintentional memory exercise for the student. A few 

 lines below, it is stated that " it is usually obtained by 

 the action of HoSO^ or HCl on Zn or on Fe (see note, 

 p. 183)." At this page we find a jar of hydrogen is 

 required for an experiment (to extinguish burning phos- 

 phorus with), and in a note a method by which hydrogen 

 "may be prepared " is given, with far too little description 

 for a beginner and far too much for anyone else. We 

 venture to predict that before many students have worked 

 through this volume, one will be found to march off with a 

 jartothe "gas-works " to get it filled with hydrogen, with 

 the full conviction that he is carrying out, if not the specific 

 instructions before him, at least an alternative way set 

 down in the book to get his hydrogen to extinguish his 

 phosphorus with. 



There is a large measure of truth in the old saying 

 that "example is better than precept," and this when 

 translated into chemical language tells us that " experi- 

 ment is better than theory." Theories in chemistry are 

 of no use whatever to the student except as they enable 

 him to remember, classify, and utilize his facts ; and if 

 the theories are to be divorced from the facts, or if 

 the facts are only to be introduced as if they were acci- 

 dental illustrations of the theories, then the study of— so- 

 called— chemistry becomes as useless as the study of the 



dead languages. We consider that any method of teach- 

 ing that tends to lead the student of chemistry to regard 

 the theories he has to learn as anything more than 

 suggestions that will be of assistance to him, is calculated 

 to injure whatever of scientific capability he may possess. 

 Good and useful theories have been believed in, and they 

 have had to be modified, enlarged, or rejected as the 

 growing richness of facts has demanded more extensive 

 ideas. To teach the theories without the facts is to 

 teach the fallible side of the science, and to make the 

 theories more important than the facts is to attempt to 

 balance a pyramid upon its apex. 



OUR BOOK SHELF. 



Treatise on Meteorological Apparatus and Methods. By 

 Cleveland Abbe, A.M. (Washington : Government 

 Printing Office, 1888.) 



Meteorological observations have been made more 

 or less continuously since the days of Ferdinand II., 

 Grand Duke of Tuscany, who first organized systematic 

 observations in the year 1653. A full account of the pro- 

 gress which has been made since then in securing data of 

 greater accuracy is contained in the book before us, which 

 forms the forty-sixth appendix to the Report of the Chief 

 Signal Officer to the United States Government. There 

 are five different sections, one being devoted to tempera- 

 ture, one to pressure, one to atmospheric movements, one 

 to aqueous vapour, and the last to the measurement of 

 rain and snow. Each section commences with a general 

 statement of the object to be attained, then the formulas 

 for correction are discussed, and finally there are descrip- 

 tions of the most accurate instruments which are at 

 present available. Every form of meteorological in- 

 strument hitherto conceived seems to find a place in 

 this wonderfully complete treatise. Besides the ordin- 

 ary instruments, all the self-recording arrangements are 

 described, and their relative merits discussed. Diagrams 

 of most of the instruments are also given. Those who have 

 but a slight acquaintance with the subject will no doubt 

 be surprised at the number of different methods of deter- 

 mining the same data, and at the number of corrections 

 which it is necessary to make before the results can lay 

 claim to scientific accuracy. The methods and standards 

 adopted by the International Bureau of Weights and 

 Measures are fully considered in every case where they 

 are applicable. 



The treatise will be invaluable to all meteorologists, and 

 will undoubtedly do a good deal towards extending the 

 usefulness of meteorological observations generally. Other 

 treatises on optics, electricity, and actinometry are to 

 follow. 



New Zealand of To-day. By John Bradshaw. (London: 



Sampson Low, 1888.) 

 Round about New Zealand. By E. W. Payton. (London : 



Chapman and Hall, 1888.) 

 In each of these books there is a full and interesting 

 account of the present condition of New Zealand. Mr. 

 Bradshaw's indignation has been excited by some of the 

 hasty judgments expressed by Mr. Froude in " Oceana," 

 and " New Zealand of To-day " may be regarded as to 

 some extent an answer to Mr. Froude's criticisms. Mr. 

 Payton's book consists of " notes from a journal of three 

 years' wanderings in the Antipodes," and the impression 

 produced by his narrative is not essentially different from 

 that of Mr. Bradshaw's more polemical work. Both 

 writers believe strongly in the future of New Zealand, 

 and express warm admiration for the great results already 

 achieved by the colonists. Yet it cannot be said that 



