SULPHOCYANIDE OF MERCURY. 
581 
the 2nd instant, in further reference to the penalty incurred by the sale in single 
powders of the medicine known as ‘ Steedman’s Soothing Powders.’ 
“ As before stated, the law clearly renders a person liable to a penalty who 
vends this or any other patent medicine in any quantity without a stamp. 
“ A case has been brought under the notice of the Board, in which it was re¬ 
presented that the purchasers of single powders of the medicine above mentioned 
were for the most part of the very poorest class, who had not the means to pur¬ 
chase a packet at the price of Is. 1 \d., and that the privilege of obtaining the 
powders singly, if prohibited, would be regarded by them as a very great hard¬ 
ship. 
“ Having fully considered the representation then made, the Board felt dis- 
posed not to insist upon a strict compliance with the law, if a single powder of 
this medicine were sold without a stamp, under circumstances similar to those 
above stated, provided that the packet from which the pow r der had been taken 
was duly stamped. 
“ I am, Sir, your obedient servant, 
“ T. Sargent.” 
SULPHOCYANIDE OF MERCURY—PHARAOH'S SERPENTS. 
OLEATE OF SODA AND SOAP BUBBLES. 
In the January number of this volume, allusion was made to this salt, and its use as 
a toy. An esteemed correspondent, whose experience in the manufacture of this salt 
has rendered him familiar with it, has sent us the following information, which he de¬ 
sires to be anonymous. Take of anhydrous prussiate of potash (ferrocyanide of potas¬ 
sium), in fine powder, 184 parts; salt of tartar (carbonate of potassa), well dried, G9 
parts; sublimed sulphur, clean and dry, 128 parts; finely-powdered charcoal, G parts ; 
mix them thoroughly, seeing that there are no lumps of aggregated powder, which ob¬ 
ject is best accomplished by sifting; and a little extra care in getting the materials 
thoroughly pulverized and mixed will be amply repaid by the purity of the product. 
Place the powder, thus prepared, in an iron vessel, and heat gently (not quite to red¬ 
ness) ; when the edges and bottom of the mass become fused to about the depth of half 
an inch, stir it thoroughly and rapidly with an iron rod, so as to melt the whole down 
as soon as possible. When it ceases to flame, and reaches a state of nearly tranquil fu¬ 
sion, which is attained at a heat materially below redness, it is to be cooled ; then dis¬ 
solved in about six or eight times its weight of water, and filtered or strained to separate 
the insoluble sulphuret of iron. The clear solution may be considered to be a tolerably 
pure solution of sulphocyanide of potassium (K,CySo), though there are always small 
quantities of secondary products formed. 
The rationale of the process is probably as follows:—The reaction being between 1 
equivalent of dry ferrocyanide of potassium, 1 equivalent of carbonate of potassa, 
8 equivalents of sulphur, and 1 of carbon; the potassium and the cyanogen of the fer¬ 
rocyanide, the potassium of the carbonate, and 6 equivalents of the sulphur unite to 
form 3 equivalents of sulphocyanide of potassium, 3 (KCyS 2 ), the iron of the ferrocya¬ 
nide and the remaining sulphur form the insoluble sulphuret of iron, whilst the carbon, 
assuming the oxygen of the liberated potassium, passes off with the carbonic acid as 
carbonic oxide, and is burnt during the process. 
Having now a solution of sulphocyanide of potassium, the next step is the solution of 
pernitrate of mercury (HgCL,2 N0 5 ), which is obtained by dissolving mercury in hot 
nitric acid, and heat until a drop of the solution will not form a precipitate with a solu¬ 
tion of chloride of sodium. The solution should then be diluted with water, until each 
ounce of mercury used is represented by a pint and a half of the solution. 
The solution of sulphocyanide of potassium is then poured gradually into the mercuric 
solution as long as a precipitate is formed, and no longer (as the mercurial sulphocyanide 
is soluble in the solution of nitrate of mercury, when in excess). The precipitate is 
heavy and subsides rapidly; it is washed in several (three or four) w'aters by subsidence 
and decantation, then the creamy sediment transferred to a muslin cloth and squeezed, 
gently at first, and then more forcibly, and the lump of moist sulphocyanide of mercury, 
