440 



Dr. J. E. Reynolds on a New Group of [Apr. 20, 



If we admit the existence of these salts in the solutions examined, they 

 might be named di-aceto-mercurates, or probably di-keto-mer •curates, the 

 latter name being used as a general term. 



e. Detection of Acetone in the " Methylated Spirit" of Commerce. — 

 Since acetone is, according to my experience, invariably present in the wood- 

 spirit of commerce, the reaction with mercuric oxide in presence of potas- 

 sium hydrate, already described, becomes virtually a test for the presence 

 of pyroxilic spirit in any mixture. The ordinary <£ methylated spirit !) of 

 commerce is such a mixture, and the acetone present in it can be detected 

 with great facility in the following way : — Take 200 cub. centims. of the 

 spirit and rapidly distil off 50 cub. centims. ; dilute the distillate with an 

 equal volume of water, and slightly warm with addition of a few cub. centims. 

 of solution of potassium hydrate. On cautious addition of mercuric chloride, 

 the oxide first thrown down is speedily redissolved : excess of the mercuric 

 salt must be carefully avoided. The alkaline liquid should be filtered clear, 

 much of the alcohol allowed to evaporate slowly, and the residue then di- 

 vided in two portions. One part is to be violently boiled for a few minutes ; 

 a yellowish-white gelatinous precipitate will suddenly make its appearance, 

 if the acetone compound be present. In the second portion, dilute acetic 

 acid, when added in slight excess, should produce a bulky, white, gela- 

 tinous precipitate containing, when washed and completely dried, between 

 78 and 79 per cent, of mercury. 



Finally, by means of the above test the admixture of " methylated 

 spirit" with alcoholic solutions may be detected with facility. In all 

 such cases, however, a specimen of a pure alcoholic solution should be 

 tested at the same time as the suspected sample, distillation of considerable 

 quantities of the liquids being resorted to in every instance. 



2. Bodies containing Mercury and higher members of the Fatty Ketone 

 series. — Experience has proved that several ketones of the fatty series are 

 capable of uniting with mercuric oxide in the presence of alkali to form 

 compounds analogous to that obtained with acetone. The higher ketones 

 being insoluble in water though soluble in alcohol, it was found to be ex- 

 tremely difficult to prepare the colloidal hydrates or hydrosols of the mer- 

 curic compound. 



In the case of butyrone, however, I have succeeded completely in ob- 

 taining a hydrosol. 



The general reactions of the several solutions leave no doubt that the 

 compound contained in each belongs to the group of colloid bodies and not 

 to that of crystalloids. 



The following results have been obtained : — 



(a) With Propione. — The rectified product of the careful destructive 

 distillation of barium propionate was dissolved in alcohol and mercuric 

 chloride added ; excess of strong aqueous solution of potassium hydrate 

 was then poured in ; on gently warming the mixture the mercuric oxide 

 dissolved in great part. The liquid, filtered as clear as possible, was found 



