TOWERS AND TANKS FOR WATER-WORK'S. 



The supply-pipe is 20 ins. in diameter, and is provided 

 with a gate, enclosed in a rectangular chamber, formed by 

 bolting together two flanged iron castings. The following has 

 been subsequently obtained through correspondence : 



"Referring to the tank concerning which you make en- 

 quiry, and upon the preservation of which is by some errone- 

 ously attributed our existence as a corporation, I beg to say 

 in reply to your request for information, that we are unable to 

 furnish any, as the property upon which the tank is situated 

 is, and has been, leased for many years." 



According to a compilation of statistics published by ' ' The 

 Manual of American Water- works/' for 1897, there are in 

 the United States 3215 complete municipal water-supply 

 plants. Of these 2223 are designed for gravity supply from 

 earth or masonry reservoirs or impounding basins, small 

 wooden tanks, or intended to be operated entirely by direct 

 pressure. 



Their Present Extent and Character. Nine hundred and 

 ninety-two works are equipped with some form of elevated 

 metallic storage-tanks or reservoirs, approximately 30 per cent, 

 of the entire number of plants, whilst 535> or about 50 per 

 cent, of these last have been erected since 1890, the figures 

 pointing clearly along what lines advanced practice in water- 

 works design is tending. 



The accompanying table, compiled from the " Manual " for 

 '97, shows to what extent each State has adopted metallic 

 reservoirs, their average diameter and height, and a record of 

 the material used in the construction as far as given. A col- 

 umn of low, or domestic, pressure, and one showing the fire, 

 or emergency, pressure is also added. The summation and 

 average of the columns of figures given is interesting in its in- 

 dication of the general practice and requirements deemed 

 necessary, and from which the composite stand-pipe is 20.2 

 ft. in diameter, with a height of 62.7 ft., capable of containing 



