170 



NATURE 



[October 15, 19 14 



to value, some new departures are certainly of 

 more value than others, but the value is relative, 

 not absolute ; it is in relation to the particular 

 exigencies of the species. We agree with the 

 author that a variation may be established, though 

 it is not of individual value ; thus, as Darwin 

 clearly stated, a variation in the direction of 

 greater parental care may become a race-saving 

 specific character, but its value is always in re- 

 lation to particular conditions of life, i.e. in 

 relation to the selection that goes on. To say that 

 Natural Selection is thus controlled is arguing in 

 a circle. 



Dr. Mottram has an excellent chapter on the 

 values of conspicuousness, whether of move- 

 ment, form, sound, scent or colour; and he has 

 the courage to uphold the thesis — the converse of 

 Wallace's — that "the male becomes brilliant in 

 colour in order that he may be more likely to be 

 destroyed : and thus the dull-coloured female gain 

 protection " ! This would naturally lead to the 

 elimination of the more brilliant males, but for- 

 tunately they mate before they are killed, so that 

 their brilliant qualities are handed on ! It would 

 be equally easy to suggest that the character which 

 is established is not merely conspicuousness, but 

 conspicuousness plus such agility that the gay 

 fellows are never caught. We think that the 

 author should re-consider his theory. As a lover 

 of birds, by the way, he should not have passed 

 such a large number of disfiguring misprints in 

 their proper names — we counted ten without look- 

 ing for them. 



OUR BOOKSHELF. 



Clean Water and How to Get It. By Allen 

 Hazen. Second edition, revised and enlarged. 

 Pp. xii + 196 + plates. (New York: John 

 Wiley and Sons, Inc. ; London : Chapman and 

 Hall, Ltd., 1914.) Price 6s. 6d. net. 



We are glad to see a second edition of Mr. Allen 

 Hazen 's useful little book on water purification. 

 There are still the interesting chapters describing 

 the various sources of supply and methods of 

 purification, and considerable space is devoted to 

 the problems arising from the tastes and odours 

 developing in water through stagnation and the 

 growth of organisms. Other chapters relate to 

 statistics of supply in different cities, and sug- 

 gestions are made as to the relative sizes of the 

 several parts of a water works which would be 

 useful in designing a new supply. 



New chapters have been added dealing with 

 the "red water" problem, and with the disinfec- 

 tion of water supplies, and it is unfortunate that, 

 with regard to the latter question the author has 

 not gone into the subject more fully, as it is a 

 question which has recently received a great deal 



NO. 2346, VOL. 94] . 



of study, both in this country and more particu- 

 larly in the United States. 



Two omissions immediately occur to the English 

 reader, the first being that the author fails to 

 recognise the pioneer work done in this country 

 by Dr. Houston and others on the use of hypo- 

 chlorites as sterilising agents, and does not 

 mention at all that the first time these substances 

 were used on any considerable scale was at Lin- 

 coln in 1905, when in consequence of a serious 

 epidemic of typhoid fever the whole of the water 

 supply was continuously sterilised with sodium 

 hypochlorite by Dr. Houston for more than a 

 year with remarkable success. 



The other point is that no mention whatever 

 is made of the now well-known "excess lime" 

 method of sterilisation of Dr. Houston, which 

 was first described by him in 1912 in his reports 

 to the Metropolitan Water Board, and has since 

 been successfully applied to several water supplies 

 both in this country and in the United States. 



The book is well illustrated with photographs, 

 and Is worth a place on the bookshelf of every- 

 one engaged in the scientific study of water 

 supply. D. B. B. 



The Vaccination Question in the Light of Modern 



Experience: An Appeal for Reconsideration. 



By Dr. C. K. Millard. Pp. xviii + 243. 



(London : H. K. Lewis, 1914.) Price 65. net. 

 Dr. Millard's book is carefully and well written^ 

 and with authority ; and the general plan of it is 

 very good. He believes, absolutely and pro- 

 foundly, in the power of vaccination to safeguard 

 each of us against smallpox ; and he is outspoken, 

 as he ought to be, over the folly of all who deny 

 this fact. But he feels, very strongly, that the 

 " Leicester experiment " — the rigorous constant 

 notification, isolation, surveillance of contacts, 

 sanitation, emergency vaccination, and so forth— 

 has been a success, not a failure. He points 

 out, very truly, that the danger is less from 

 severe cases than from slight, "masked," un- 

 recognised cases ; and these cases often occur in 

 persons lightly and Inadequately vaccinated to 

 satisfy the law. He tells the dreadful story of 

 Dewsbury and of Gloucester, where the people had 

 Leicester's anti-vaccination spirit without Leices- 

 ter's sanitation. The main purpose of his book 

 is to underline the difference between vaccination 

 as a personal safeguard and vaccination as a civic 

 safeguard. 



The whole book is of singular interest. It is 

 open to criticism here and there. The author does 

 not lay enough stress on the fact that evil or 

 fatal effects from non-aseptic vaccination belong, 

 nearly all of them, to a time which is happily over 

 and done with. He does not sufficiently reckon | 

 with the chance of contact cases escaping from 

 surveillance and flitting outside the cordon. It 

 may be, also, that he ought to make more allow- 

 ance for the possible surprise of the disease flaring 

 up with unexpected virulence of type : we must 

 be very careful how we talk of a disease "dying 



