NATURE 



525 



TOWERS AND TANKS FOR WATER-SUPPLY. 

 Towers and Tanks for Water- Works. The Theory and 



Practiee of their Design and Construction. By J. N. 



Hazlehurst. Pp. ix + 216. (New York: John Wiley 



and Sons ; London : Chapman and Hall, Ltd., 1901.) 



Price \os. 6d. 



THIS book deals exclusively with a special subject 

 relating to water-supply, namely, the design and 

 construction of metal stand-pipes and tanks for storing 

 up water at a sufficient elevation to provide adequate 

 pressure for its proper distribution. An illustration of a 

 stand-pipe, 20 feet in diameter and 120 feet high, at St. 

 Augustine, Florida, is given in the frontispiece ; and a 

 view of a high cylindrical tank raised on a tower, or 

 more strictly a trestle, consisting of light metal standards 

 braced together, erected for the water-supply of West 

 Tampa, Florida, is shown opposite p. 116; and these 

 two examples very fairly indicate the structures which 

 form the subject of the volume. These stand-pipes and 

 tanks, besides serving as reservoirs for the storage of an 

 adequate supply of water to meet any sudden increased 

 demand, and admitting of a temporary suspension of the 

 pumping, are also valuable as regulators of the distribu- 

 tion, and as relief-valves for preventing the occurrence of 

 undue stresses in the pipes in the process of pumping. 



A considerable number of municipal water-works in 

 the United States have been furnished with some form 

 of metallic reservoirs, especially within recent years, in 

 places where there is not a suitable site at a sufficient 

 elevation for the construction of an ordinary reservoir of 

 earth or masonry. Thus, out of more than three thousand 

 complete municipal water-works in the United States, nine 

 hundred and ninety-two have been equipped with elevated 

 metallic reservoirs, five hundred and thirty-five of which 

 have been erected since 1S90. These structures exhibit 

 great variety in their dimensions ; for the largest tank 

 in the United States, erected at Greenwich, Connecticut, 

 in 1889, is made of wrought iron, 80 feet in diameter and 

 35 feet high, having a capacity of nearly 1,320,000 

 gallons, and rests on a concrete foundation ; \vhilst a 

 steel stand-pipe erected at Winona, Minnesota, in 1876, 

 has a diameter of only 4 feet, and a height of 210 feet,* 

 with a capacity of 20,000 gallons, and rests upon a 

 masonry foundation 18 feet thick. 



Stand-pipes are by far the most common form of 

 metallic reservoirs adopted in the United States, exceed- 

 ing eight hundred in number ; but steel tanks supported 

 at the requisite height on steel trestles are now very 

 often preferred, as a cheaper and safer way of supporting 

 the eftective upper column of water, 20 to 30 feet high, 

 than by a column of water below enclosed in a cylinder ; 

 and already one hundred and sixty-one such tanks have 

 -been erected, most of them since 1S90. The stand-pipes 

 vary, for the most part, from 50 to 120 feet in height and 

 from II to 39 feet in diatneter, being exposed to maximum 

 pressures of 82 to 130 lbs. ; whilst their average dimen- 

 sions and pressures are, 63 feet height, 20 feet diameter, 

 with a capacity of 150,000 gallons, an ordinary pressure 

 in the distributing pipes of 62 lbs. per square inch, and 

 NO. 1665, VOL. 64] 



an emergency pressure of 104 lbs. The tanks, on the 

 average, have a height of 37 feet, a diameter of 21;^ feet, 

 a capacity of 101,000 gallons, and an elevation on a 

 trestle, or tower, of 63^ feet. To obtain the average 

 pressure of 62 lbs., the effective height of the stand-pipe 

 or tank would require to be 142 feet ; but generally 

 advantage can be taken of some natural elevation in the 

 neighbourhood to reduce the actual height of the stand-pipe 

 or tank. A chapter is devoted to the design of each of 

 these structures, dealing also, in the case of stand-pipes 

 with the bed-plate, connections, stiffener at the top against 

 wind, and anchorage, and in the chapter on tanks, with 

 wind-bracing and anchorage. 



The author, however, leads up to the subject of design 

 by five preliminary general chapters, on the chemical and 

 physical properties of wrought iron and steel, the relative 

 merits of these metals, the stability of structures, me- 

 chanical principles, and riveting ; and after the two 

 chapters on designing, he proceeds to deal, in three 

 successive chapters, with foundations, painting, and shop- 

 practice and erection. Accordingly, the book embraces 

 a wider range of subjects than might be anticipated from 

 its title ; and by a very comprehensive treatment, a 

 complete guide is provided for the design and construc- 

 tion of a special class of structures, of limited application, 

 which have not hitherto received adequate consideration. 



ELEMENTARY ZOOLOGY. 

 Animal Life : a First Book of Zoology. By President 

 D. Starr Jordan, Ph.D., LL.D., and Prof V. L. Kellogg, 

 M.S. of Leland Stanford Junior University. Pp. ixH- 

 329. (London : H. Kimpton, 1901.) 



THIS volume is one of the twentieth century text-book 

 series, and adds another to the rapidly growing stock 

 of elementary science manuals. It contains more than 

 300 pages, with 180 text figures, and its only novelty is 

 the method of treatment, the authors combining the 

 most elementary detail with the most abstruse ideas set 

 forth in simple language. The reason of this is their 

 conviction that " the veriest beginner ought to be an 

 independent observer and thinker," and that " the 

 point of view which the zoological beginner should take 

 is the point of view that the best and most enlightened 

 zoological scholar takes." 



There are si.xteen chapters to the book, with a brief 

 classification and a glossary. The lives of the simple 

 and the more complex organisms are first dealt with, 

 then come chapters on multiplication and sex, on function 

 and structure, on the life cycle, and so on. The struggle 

 for existence, adaptation, commensalism and symbiosis, 

 parasitism, protective resemblance, and other topics are 

 all in turn considered, and the whole closes with a 

 chapter on distribution. 



There are incorporated in the book a selection of the 

 elementary facts and the commonplaceisms of the 

 modern fantasies of zoology. Both are reasonably dealt 

 with, but we find nothing for very especial comment. 

 Novelty mainly attaches to some of the illustrations ; for 

 example, the frontispiece — a photograph of a group of 

 red-faced cormorants — a companion plate of a family of 

 fur seals, a striking picture of the angler fish (Coryno- 

 lophus) enticing its prey (not lighting up the sea-bottom 



Z 



