Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/247

 of this residue being treated with muriatic acid and oxalat of ammonia, oxalat of lime was precipitated ; and another portion being treated with neutral carbonat of ammonia and phosphat of soda, some magnesia was precipitated in the form of triple phosphat, circumstances which confirmed the presence of lime in the form of selenite, and that of magnesia, in the form of sulphat or Epsom salt.

2. The alcoholic solution being evaporated to dryness, a yellowish deliquescent residue was obtained, which, being dried at 160° weighed 0,9 grains. Water being added to this residue, a small portion of it remained undissolved. The filtered watery solution was yellowish, though perfectly transparent, and being examined by the usual reagents, appeared to contain iron, sulphuric acid and muriatic acid, with imponderable vestiges of lime and magnesia, without any trace of alumine.

3. From these circumstances, it was inferred that the only deliquescent salts yielded by the residue, in ascertainable quantities, were sulphat of iron, and muriat of iron, both of which had probably been formed in consequence of some new orders of attraction taking place during the process of evaporation to which the water had been subjected.

1. The presence of magnesia was ascertained beyond all doubt, in the following manner:

50 grains of residue minutely pulverized, were boiled in a solution of neutral carbonat of ammonia, so as to decompose all the