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In their initial experiments, he and his team created a standardised manure-like stench from a mixture of dimethyl disulphide, dimethyl trisulphide, diethyl disulphide, butyric acid, para-cresol and guaiacol.

On acidifying the solution so obtained with hydrochloric acid, the whole of the arsenic is reprecipitated as trisulphide, K2HAsO3 + K2HAsS3 + 4HCl = 4KCl + 3H2O + As2S3.

Arsenic pentasulphide, As2S5, can be prepared by fusing the trisulphide with the requisite amount of sulphur; it is a yellow easily-fusible solid, which in absence of air can be sublimed unchanged; it is soluble in solutions of the caustic alkalis, forming thioarsenates, which can also be obtained by the action of alkali polysulphides on orpiment.

In the wet way, arsenious oxide and arsenites, acidified with hydrochloric acid, give a yellow precipitate of arsenic trisulphide on the addition of sulphuretted hydrogen; this precipitate is soluble in solutions of the alkaline hydroxides, ammonium carbonate and yellow ammonium sulphide.

Antimony trisulphide, Sb2S3, occurs as the mineral antimonite or stibnite, from which the commercial product is obtained by a process of liquation.