–nitrogen gas, 234;

sulphuretted hydrogen, 235;

carburetted hydrogen, 236;

carbonic acid, 237;

sulphuric acid, 238;

sulphate of magnesia, 241;

sulphate of iron, 243.

—, Erie canal route, gases and acids in the vicinity of, A. Eaton, xv, 233;

sulphate of alumina, 243;

carbonate of iron, 244;