[page] 302

TANKS AND HOSE: C R D would be glad of information on the following point, and it might be useful to others as well as himself. He intends making a large tank, and has three others, much smaller but deeper tanks, standing on the same level or a little lower, which he wants to have the power of filling from the large tank. The distance between the two furthest tanks is about 180 feet, but not in a quite straight line; the deepest tank is 21 feet. Now, can any one tell him whether a syphon made of Burgess and Keys' canvas hose, lined and coated with gutta percha,¹ or of any other material, would practically answer? What bore should the syphon have, to convey in the course of 10 or 12 hours 3000 gallons of water?² [It depends altogether on the difference of level between the water in the one tank and that in the other. The syphon may be filled easily, if one end be placed in one tank, and a hand garden syringe tied to the other end, which would soon pump it full.]

¹ A kind of rubber, used to insulate the first undersea telegraphy cable in 1850.

² See Correspondence vol. 5, p. 138. There was one response in Gardeners' Chronicle, no. 20, 14 May 1853, p. 318.