328 Fdrmation of Minerals in the Humid Way. 



crystals. Red copper ore, or red oxide of copper, in red, shining, 

 translucent octahedrons. 



Carbonates, — Carbonate of magnesia. Carbonate of iron. Car- 

 bonate of manganese. Carbonate of cobalt. Carbonate of nickel. 

 Carbonate of zinc. Malachite, or carbonate of copper. 



Sulphates. — Sulphate of baryta, in the primitive form. 



Sulphurets. — Realgar, in transparent crystals, with the colours, 

 lustre, and form, as in mineral veins. Sulphuret of antimony, in 

 acicular, shining, metallic-looking crystals. Sulphuret of bismuth, 

 with similar characters as the preceding. Sulphuret of iron. Sul- 

 phuret of manganese. Sulphuret of cobalt. Sulphuret of nickel. 

 Sulphuret of zinc. Sulphuret of copper. These last mentioned are 

 massive, as is the case with those prepared in our laboratories ; but 

 it appears that the hydrosulphuric acid, under certain conditions of 

 temperature and pressure, is a solvent of sulphurets, and a general 

 agent of crystallisation. The properties of this acid explain the ac- 

 cumulation of metallic sulphurets in the deep parts of mineral repo- 

 sitories, and of metallic carbonates near their crop or outgoings. 



Arseniosulphurets. — Mispikel in crystals, with the colour, lustre, 

 and form of that found in mines. Red arsenical silver, having all 

 the characters of the natural mineral. 



Antimoniosulphurets. — Red antimonial silver, in large crystals. 



Conclusions. 



I had proposed to establish, upon experimental proofs, the con- 

 troverted, and, as I think, very probable opinion, which attributes 

 the filling up of the concretionary veins to incrusting thermal depo- 

 sitions, and to shew that the formation of a great number of minerals 

 which we there meet, whether they be crystallised or amorphous, do 

 not always presuppose conditions or agents far removed from the 

 actual existing causes. 



We thus, in fact, perceive that the two principal elements of the 

 most widely -extended thermal springs, the sulphurets and the alka- 

 line bicarbonates, have sufficed to produce twenty-nine distinct mi- 

 neral species, almost all crystallised, belonging to the native metals, 

 to the oxides, to the carbonates, to the sulphates, to the sulphurs, 

 to the oxy sulphurets, to the sulpho-arseniates, to the sulpho-antimo- 

 niates, in a word, to all the great families of the chemical compounds 

 peculiar to concretionary beds, each of which has some representa- 

 tives in my experiments. ■"• '" 



Means of synthesis equally simple, applicable however" ibr<($tim- 

 pounds as variable, give certainly a great probability to the speculative 

 ideas which have directed me in these researches. It will, moreover, 

 be necessary to diversify them to a much greater extent ; and when we 

 shall in the same manner have studied the different chemical agents, 

 and the influences of every kind which can modify their eff'ects, we 

 shall undoubtedly succeed in defining the probable condition of the 



