NATURE 



97 



THURSDAY, JUNE i, 1905. 



PUBLIC HEALTH AND SEWAGE 

 PURIFICATION. 



Sanitary Law and Practice. A Handbook for 

 Students. By W. Robertson, M.D. (Glas.), D.P.H., 

 and Charles' Porter, M.D., B.Sc. (Public Health), 

 M.R.C.P. Edin. Pp. xiii + 756. (London: Sani- 

 tary Publishing Co., Ltd., 1905.) Price los. 6d. 

 net'. 



The Sewage Problem. A Review of the Evidence 

 Collected by the Royal Commission on Sewage 

 Disposal. By Arthur J. Martin, .^ssoc.M.Inst.C.E., 

 M.R.San.L Pp. xvi + 363. (London: Sanitary 

 Publishing Co., Ltd.) Price 8i. 6d. net. 



Simple Methods of Testing Seivage Effluents. For 

 Works Managers, Surveyors, &c. By George 

 Thudicum, F.LC. Pp. 60. (London : Sanitary 

 Publishing Co., Ltd., n.d.) Price 2s. 6d. net. 



THE official responsibility for the safeguarding of 

 the public health rests mainly with the repre- 

 sentatives of four professions, viz. the medical officer, 

 with his colleague the sanitary inspector, the bacteri- 

 ologist, the engineer, and the chemist. A study of 

 the volumes under review has strengthened the belief 

 that it is desirable that members of each profession, 

 while working cordially together for a common end, 

 should severally recognise their respective limitations. 

 The te.\t-book on " Sanitary Law and Practice " by 

 Drs. Robertson and Porter is written in sections, each 

 section referring to some special branch of public 

 health work. A considerable portion of each section 

 is occupied by a digest of the legal enactments affect- 

 ing the subject, this being followed by paragraphs 

 dealing, by description and advice, with the practical 

 duties of the health officer. The condensation of 

 legal information, so far as can be estimated by 

 references to special points coming under the ex- 

 perience of the reviewer, is done with judgment, and 

 constitutes a feature of the book, of great value alike 

 to the student and to the practitioner. 



Many useful hints from the wide experience of the 

 authors are to be found in the descriptive portions 

 of the book. Their experience, however, is naturally 

 not all-embracing, and it is not difficult to note where 

 their information is derived from the statements of 

 others. 



The subject of destructors, although coming within 

 the province of the engineer, is evidently one with 

 which the authors are familiar. The descriptions are 

 clearly written, and the essential points in construc- 

 tion, choice of site, and proper management well 

 brought out. 



In the section on food and drugs no attempt is 

 made to instruct the medical officer in duties which 

 properly belong to the public analyst. This is satis- 

 factory in view of the attempt frequently made by 

 small authorities to combine the offices of public 

 analyst and medical officer. Even in such a com- 

 paratively simple matter as the analysis of a sample 

 of water, which in the chapter on water supply 

 (p. 433) is referred to as part of the medical officer's 

 NO. 1857, VOL. 72] 



duties, unsuspected pitfalls may lurk. It is doubtful 

 whether bacteriological examinations should ever be 

 undertaken by any but a trained bacteriologist, at 

 any rale where identification of a given species is 

 required. 



In the section on disinfection a questionable 

 prominence is given to the use of sulphur. The 

 authors themselves, in a later paragraph, deprecate 

 the use of superheated steam as being " no better 

 than a gas," and in view of the obvious disadvantages 

 in the use of sulphur, which have given rise to serious 

 complaint of destruction of fabrics and fittings, 

 especially on board ship, it can hardly be compared 

 with liquid disinfectants such as formalin. No refer- 

 ence is made to the use of hypochlorites, which in 

 certain circumstances have been found to give excel- 

 lent results. 



A wise reserve is maintained on the vexed question 

 of sewer ventilation, a qualified approval being given 

 to upcast shafts. It is unfortunate that a similar 

 reserve has not been exercised in the chapter on 

 sewage purification. In a book intended for students 

 it is unwise to select, even for description, any form 

 of patented appliance which is not thoroughly estab- 

 lished. The choice for special commendation of one 

 particular patented apparatus, concerning the merits 

 of which competent opinion can at least be said to 

 be divided, is certainly to be deprecated. A clear ex- 

 position of general principles of sewage treatment 

 would have been more valuable. 



This leads to the consideration of the able con- 

 densation of the bulky volumes of evidence given 

 before the Royal Commission on Sewage Disposal 

 which is to be found in Mr. Martin's book on the 

 " Sewage Problem." Mr. Martin has provided a 

 book which will be eagerly sought after by members 

 of sewage committees and others who are appalled 

 at the mass of matter in the numerous blue-books 

 published by the commission. He is to be congratu- 

 lated upon the impartial way in which he has mar- 

 shalled the evidence. Possibly because of this im- 

 partiality the impression left upon the reader is that 

 in spite of the great amount of work that has been 

 done on the subject, sewage purification is still rather 

 an art than a science. 



The Royal Commission has been criticised for the 

 slowness of its methods. .-X more just criticism would 

 be that it might have devoted more energy to ques- 

 tions affecting the theory of the processes in use. As 

 it is, a mass of empirical and sometimes conflicting 

 information has been accumulated, from which it is 

 extremely difficult to extract underlying certainties. 

 While fully realising that a large part of the sewage 

 problem is concerned with purely practical questions of 

 cost and local conditions, yet ultimately the economic 

 solution must depend on a full knowledge of the 

 changes taking place in the course of various methods 

 of treatment ; and these are as yet by no means per- 

 fectly understood. It is curious, e.g., that no witness 

 deals in any detail with the purely physical effects 

 produced by contact with the filtering medium, 

 although many observers, especially on the Continent, 

 believe that these play a very large part in connection 

 with the changes produced. It is by no means 



F 



