CISTEKNS. 



To find the number of gallons in square or oblong square 

 cisterns. 



RULE. Multiply the length in inches by the width in 

 inches, and that by the depth in inches, and divide the pro- 

 duct by 231. The quotient will be the number of gallons. 



EXAMPLE. Given, a cistern 6 feet long by 3 feet wide 

 and 4 feet deep ; how many gallons will it contain ? 



SOLUTION. 72 inches, length, x 36 inches, width, x48 

 inches, depth, = 1244164- 231 =538.59 galls. Ans. 



To Jmd tJie number of gallons in triangular cisterns. 

 c 



/is 



RULE. Multiply the base a b in inches, by the perpen- 

 dicular height c d in inches, and half that sum by the depth 

 in inches, and divide the product by 231. The quotient 

 will be the number of gallons. 



EXAMPLE. Given, a triangular cistern 8 feet at the base 

 or longest side, 7 feet in perpendicular height, 4 feet deep. 

 How many gallons will it contain ? 



