July 19, 1901.] 



SCIENCE. 



105 



streams, chemical aud bacterial examiuatious, 

 and the diseases caused by impure water. Part 

 II., cousisting of 5-19 pages, treats of hydraulics, 

 works for the collection and storage of water, 

 purification systems, aud the methods of distri- 

 bution by tanks, pipes and pumps. The space 

 devoted to the different topics appears well 

 proportioned to their relative importance, the 

 subjects themselves are usually thoroughly 

 treated and descriptions of the most modern 

 practice are freely given. 



The question of economy in engineering con- 

 struction is a controlling one in all comparative 

 designs, and this book is one of the few to 

 bring it prominently to the notice of the 

 student. The annual interest on the first cost, 

 plus the annual cost of operation and main- 

 tenance, is to be made a minimum, and the 

 general method of doing this is set forth clearly 

 and satisfactorily. Even in cases where the 

 general method is not of direct application, the 

 economic arrangement of details is often dis- 

 cussed. Thus, the economic size of one sand 

 filter bed is shown to depend upon the number 

 of beds, and upon the cost of walls and bottom 

 filling as compared with the cost of piping, 

 valves and other appurtenances. Such dis- 

 cussions are a characteristic of modern engi- 

 neering and their introduction into text-books 

 should be welcomed, for economic construc- 

 tion is the corner stone of sound engineering 

 practice. 



The general subject of hydraulics is set forth 

 only to a limited extent, as a full treatment 

 could scarcely be given in a single chapter. 

 The laws of flow of ground water are, however, 

 fully presented and useful formulas developed, 

 while the subject of water hammer is discussed 

 in a novel manner. Reservoirs, dams, filtra- 

 tion systems, conduits and pipes, pumping 

 machinery, and the distribution of water, are 

 well and thoroughly treated, with numerous ex- 

 amples of constructed works. In short, it may 

 safely be said that the book constitutes one of 

 the very best treatises on water-supply engi- 

 neering now before the American public. 



At the end of each chapter, with the excep- 

 tion of the brief one on hydraulics, there is 

 given a useful list of literature. Periodicals 

 are cited in italics, while transactions and books 



are in Roman type. Few engineering students 

 will know what is meant by 3yg. Bund., Cent, 

 f. Bakt., and other similar abbreviations which 

 should properly have been written out in full. 

 The book seems, however, remarkably free 

 from errors that are apt to occur in a first edi- 

 tion. The most serious ones noted are on page 

 213, where it is said that one U. S. gallon is 

 0.1605 cubic feet, and on page 216 where the 

 word ' longitudinally ' should have been ' trans- 

 versely.' The book is well j)rinted with the 

 exception of the cuts, many of which properly 

 deserve severe criticism. 



The chapter on chemical and bacterial ex- 

 aminations of water appears to be the only one 

 that is likely to prove unsatisfactory to engi- 

 neering students. Bacteria are not defined and 

 described in respect to size, form, color and 

 functions, and the impression is given that all 

 are specific germs of disease, while there is no 

 hint as to the useful work performed by many 

 species in transforming injurious decaying 

 matter into harmless constituents. At the foot 

 of page 123 a statement is made implying that 

 bacteria in water are found in the suspended 

 matter and not in solution. On page 125 it is 

 said that a water rich in bacteria is not neces- 

 sarily poor in quality. On the whole this dis- 

 cussion lacks that definiteness and logical 

 method which is demanded by engineers. The 

 chemical part of the chapter is better, but it is 

 also lacking in definiteness, as no records of 

 analyses are given and little is said which will 

 enable a student or engineer to interpret the 

 results of a water analysis. 



The field of water supply on both the sani- 

 tary and construction side has become so vast 

 that special treatises on the chemistry and bac- 

 teriology of water, filtration, reservoirs, stand- 

 pipes and distribution plants are demanded by 

 practicing engineers. For the student, how- 

 ever, such differentiation is neither feasible nor 

 desirable, and this volume, with the exception 

 above noted, presents such a satisfactory review 

 of the theory and practice of the entire subject 

 that it will undoubtedly prove of great service 

 in technical education, and at the same time 

 take high rank as a manual for young engineers. 

 Mansfield Mereiman. 



Lehigh University. 



