311onthly .Meeting of the Franklin Institute. not exceed five per day, which involves a consumption of nearly 20 tons of iron. Every pipe before leaving the foundry is subjected to a severe test by hydraulic pressure. The moulds, which stand about 13 feet high, are sunk into the ground, bringing the top of the cylinder nearly on a level with the surface. The liquid metal weighing, as already stated, about 4 tons, is brought by means of a steam crane from the melting filrnace~ and poured into the mould.