1st. _Sulphuretted carbonate of potash._ This consists of 1 atom carbonate of potash (61) with 1 atom of sulphur (14). Its analysis may be effected as follows: the quantity of carbonic acid may be found by the lime water necessary to saturate it; the potash may be known from the quantity previously entering into the mixture; and the sulphur in the same manner, or from the quantity of sulphuretted carbonate of lead that it forms.--The sulphur may also be known, from the quantity of oxygen it requires by means of oxymuriate of lime to produce saturation; this I find to take place when the oxygen is half the weight of the sulphur, or one atom to one of sulphur; it soon happens, that one atom of sulphur deprives two others of their oxygen, and sulphuric acid is formed whilst the other two atoms of sulphur join the carbonate of lime and are precipitated along with it. As it may frequently happen, that the sulphuretted carbonate is mixed with common carbonate of potash, the proportions may be found by means of nitrate of lead, which being cautiously dropped into the solution, lets fall first the brown sulphuretted carbonate of lead, and then the common white carbonate of lead. The sulphuretted carbonate of potash absorbs oxygen and precipitates metals much the same in appearance as the other sulphurets; but essential distinctions are observable, some of which are noticed above, and others will appear in the sequel. 2 and 3. The _trisulphuret_ and _quadrisulphuret_ of potash so nearly resemble the quadrisulphuret of lime in their properties, as not to require any additional remarks. _Hydrosulphuret of potash._ This combination, when duly proportioned, consists of 15 parts sulphuretted hydrogen, and 42 potash by weight, or one atom of each. It may be formed by directly uniting the two elements, or by decomposing hydrosulphuret of lime by carbonate of potash. Its properties agree with those of the other hydrosulphurets. 11. _Sulphurets of soda._ I have repeated most of the experiments on the sulphurization of potash with soda, and have not found anyone remarkable feature of distinction, besides those which arise from the weights of the atoms. 1. _Sulphuretted carbonate of soda_ consists of 1 atom of carbonate of soda united to 1 of sulphur; or of 47 parts of the former and 14 of the latter. 2. _Trisulphuret of soda_ consists of 1 atom soda (28) and 3 of sulphur (42). 3. _Quadrisulphuret of soda_ consists of 1 atom soda (28) and 4 atoms of sulphur (56). _Hydrosulphuret of soda._ This compound consists of one atom of each of the elements, or 15 sulphuretted hydrogen, and 28 soda. In other respects it agrees with hydrosulphuret of potash. 12. _Sulphuret of ammonia._