July 21, 1911] 



SCIENCE 



81 



level, while the deep streams meandering slug- 

 gishly through them do not shoal, but become 

 continually deeper through a slight excess of 

 depression of their bottoms, as a part of the 

 area of general subsidence, over the fill due to 

 sediment. This is a classic and very evident 

 proof of actual subsidence, as valid nove as 

 ever. The subsidence has probably been very 

 slow, possibly not over six inches in a century, 

 but that it is real admits of no doubt. To 

 ascribe these phenomena to the fluctuations of 

 height of ordinary high tides is, to say the 

 least, inadmissible. 



Thos. L. Casey 



SCIENTIFIC BOOKS 

 Conservation hy Sanitation. By Dr. Ellen 



H. EiCHARDS. New York, John "Wiley & 



Sons. 1911. 8vo. Pp. 305. Cloth, $2.50. 



Illustrated. 



Peculiar interest attaches itself to this 

 work, as it is almost the last publication of one 

 who has contributed very largely to the litera- 

 ture of modern sanitation. Mrs. Eichards's 

 books ,on water analysis are well known to a 

 wide circle of readers. Her other books on the 

 cost of cleanness, the cost of living, the cost 

 of food, the cost of shelter, the chemistry of 

 cooking and cleaning, home sanitation, etc., 

 are equally well known to an entirely different 

 circle of readers. To say that these books 

 have had an important influence in molding 

 modern sanitary thought, especially among 

 women, is to put the truth but mildly. 



" Conservation by Sanitation " is a labora- 

 tory guide for sanitary engineers in the study 

 of air, water supply and the disposal of waste. 

 It is divided into two parts. Part I., which 

 comprises about three quarters of the work, 

 is of a general character and adapted to a 

 wide field of readers. Its style is discursive, 

 perhaps too much so, but it covers many mat- 

 ters of interest and importance in the realm 

 of sanitary science. 



Especial prominence is given to the sanita- 

 tion of air, which is regarded as " a neglected 

 resource." The advantages of pure air and 

 better ventilation in houses and factories is 

 set forth. One chapter is devoted to the work 



of the sanitary inspector and the analysis of 

 air. 



Several chapters are devoted to the history 

 of public water supplies, the development of 

 the sanitary idea as indicated by the muni- 

 cipalization of water works, economic and 

 sanitary efficiency of water works, protection 

 of water supplies as a conservation of natural 

 resources, the regeneration of a spoiled water- 

 shed, the interdependence of town and coun- 

 try, and efficiency of filtration. On many of 

 these subjects the information given is dis- 

 jointed, but is nevertheless instructive. Par- 

 ticular emphasis is placed upon the necessity 

 of collecting water from a clean gathering 

 ground and storing it in clean reservoirs. 

 The uses of the chemical analysis of water 

 are described at length, but one of the rather 

 surprising features of the book is the con- 

 spicuous absence of references to bacteria 

 and their importance in water supplies. 



Two chapters are devoted to the disposal of 

 wastes, including garbage, sewage and wastes 

 from manufacturing establishments. The ef- 

 fect of dilution is considered at some length, 

 but little space is devoted to works for the 

 purification of sewage. 



The first part of the book closes with a 

 chapter on the education and position of the 

 sanitary engineer in the progress of modern 

 sanitation, in which emphasis is placed on the 

 need of efficiency in the enforcement of health 

 laws. 



The mechanical basis of modern life must come 

 to the aid of moral and personal influence. It is 

 not enough to teU men to do the right thing — 

 they must be fenced in from the wrong thing. 

 For this reason the public service engineer is the 

 emerging leader in community welfare. 



Part II. comprises a series of laboratory 

 exercises and tests on the inspection of ven- 

 tilation and the analysis of water and sewage. 

 These notes are based on exercises prepared 

 for the fourth-year sanitary engineering stu- 

 dents at the Massachusetts Institute of Tech- 

 nology, where Mrs. Richards was for so many 

 years an important member of the faculty. 



G. C. Whipple 



