TANK. 



" The importance of collecting rain 

 water for domestic purposes, espe- 

 cially in districts where springs are 

 deticienl or lie at a great depth, has 

 been much overlooked. Waistell ur- 

 ges the importance of placing spouts 

 round all the buildings of a farm to 

 collect the rain water which falls 

 upon them inco a lank or tanks, ob- 

 serving that, besides the value of the 

 supply of water thus obtained, the 

 buildings will be benefited by the 

 walls and foundations being kept 

 drier than when the water from the 

 roof is suffered to fall upon them. 

 He states that the quantity of water 

 that falls annually upon every hun- 

 dred superficial feet, or square of 

 building, is about 1400 imperial gal- 

 lons. If, therefore, the external sur- 

 faces of roofs were adapted to the 

 collection of the rain water which 

 falls upon them, and means were 

 provided for conveying it to covered 

 tanks, in which it might be preserved 

 from evaporation, and kept free from 

 any admi.xture of impurities, almost 

 every house might be readily and 

 cheaply supplied with a quantity of 

 wholesome water sufficient for the 

 ordinary wants of its inhabitants. 

 The extensive roofs of churches and 

 other public buildings might be em- 

 ployed in like way to collect water 

 for the supply of ponds or tanks for 

 public use. In some cases, even the 

 drainage of lands might also be made 

 avadable, as the water may be sub- 

 mitted to any required process of 

 filtration before it is allowed to enter 

 the tank. 



" Tanks or cisterns to hold water 

 for domestic purposes maybe conve- 

 niently situated beneath the surface 

 of the ground, so that, being paved 

 over, they occupy no valuable space. 

 They are formed of stone slabs 

 grooved into each other and set in ce- 

 ment ; of slate ; of large paving tiles 

 bedded in cement ; of brick-work ; 

 of plates of cast iron ; or of thick 

 wooden planks, protected by ciiarring 

 and pitching, or lined with stieet lead. 

 The brick tanks described by Waist- 

 ell are circular, the sides being built 

 like a well, with bottoms of an ia- 

 774 



I verted dome-shape, of very slight 

 I convexity. The top is also dome- 

 shaped, and has an opening in the 

 centre, large enough to receive a 

 man, in order that the tank may be 

 thoroughly cleaned out when neces- 

 sary. This opening, which may be 

 upon the surface of the ground, or a 

 little above it, should be covered with 

 an oak flap pierced with a number of 

 holes, or with an iron grating. The 

 depth and width of the tank should, 

 it is stated, be nearly equal. If ne- 

 cessary, a smaller brick chamber may 

 be constructed alongside of the tank, 

 in which the water may be filtered 

 through gravel, sand, charcoal, &c., 

 before entering it. It is recommend- 

 ed to make the opening by which 

 water enters the tank near the top. 

 Brick tanks of this description may 

 be rendered water-tight by laying the 

 inner course of bricks in cement, and 

 plastering the whole of the inside 

 with the same to the thickness of 

 about three quarters of an inch. To 

 enable them without injury to bear 

 the groat weight of water when near- 

 ly full, the earth should be rammed 

 closely round the brick work, and it 

 should be allowed to settle thoroughly 

 before any great quantity of water is 

 admitted. Loudon describes anoth- 

 er kind of brick tank, contrived to 

 save expense in construction, by 

 adopting a figure of maximum capa- 

 city and minimum surface. "When 

 the tank is large, it is proposed to 

 adopt the spherical form ; and when 

 of less than five or six feet in diam- 

 eter, that of a short vertical cylinder, 

 with hemispherical ends. By pud- 

 ' dling with clay round about the tank, 

 the necessity for the use of Roman 

 ! cement is avoided. 

 [ " In addition to tanks for water, 

 every farm-yard should have one to 

 ■ collect the liquid portion of the ma- 

 j nure, which is washed by the rain 

 through the refuse litter, and also the 

 urine of the stalled cattle. Though 

 not yet generally adopted, in France, 

 Germany, and especially in Belgium, 

 such tanks are considered as neces- 

 I sary to a farm as any of its most com- 

 I mon buildings. They are usually 



