December 7,1372.] THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
413 
dish, and excess of nitric acid expelled by evapora¬ 
tion nearly to dryness on the water-bath, water 
added, filtered, and the sulphuric acid in the filtrate 
determined by precipitation as sulphate of barium. 
Whether the amount of sulphate of barium obtained 
after the subtraction of that due to sulphur removed 
by bisulphide of carbon corresponded to ter- or 
penta-sulpliide of antimony was then ascertained by 
calculation. Proceeding in this way, the following 
results were obtained:— 
B.P. Product. 
No. 1. 
No. la. 
1st experiment. 
2nd experiment. 
1st experiment. 
1 2nd experiment. 
Water. 
Oxide of Antimony . 
Sulphur removed by 4 
Bisulphide of Car- /- 
bon.3 
Per cent. 
2- 97 
3- 584 
•514 
Per cent. 
2- 97 
3- 258 
•532 
Per cent. 
1-372 
35-938 
23-975 
Per cent. 
1-272 
38-515 
Per cent. 
1-272 
37-013 
25-725 
Ter- or Penta-sul- \ 
phide of Anti- > 
mony . ... ) 
7-068 
92-932 
6-760 
93-240 
61-265 
38-735 
64-010 
35-990 
Total. 
100-000 
100-000 
100-000 
100-000 
Sulphide of Antimony .— 812 gram of the B.P. 
product gave on oxidation with fuming nitric acid 
P538 gram of sulphate of barium, which is equi¬ 
valent to ‘2112 gram of sulphur. Deducting from 
this *004 gram as the proportion of sulphur (as¬ 
certained by calculation from data given in the 
table) which would be removed by bisulphide of 
carbon, there is left a remainder of '2072 gram. 
This is equivalent to '7339 gram of ter sulpiride of 
antimony, or 92T89 per cent, of the hydrated salt; 
or to '5118 gram of the pentasulpliide, or 62'29 per 
cent. The antimony compound present was ob¬ 
viously the tersulphide. 
With No. 1 and No. la, a different, and it is be¬ 
lieved, a simpler plan was adopted. '492 gram of 
the powder which remained after treating No. 1 
with solution of cream of tartar and with bisulphide 
of carbon successively, was oxidized as previously'de- 
scribed, and yielded 1'058 gram of sulphate of barium. 
Theory requires that '492 gram of Sb 2 S 3 should 
give roil gram of sulphate of barium and a similar 
quantity of Sb 2 S 5 should give 1'418 gram of the 
same salt. Proceeding in the same way with No. la, 
it was found that '218 gram gave '454 gram of 
sulphate of barium; theory requires that '218 gram 
of Sb 2 S 3 should give '448 gram, and that the same 
quantity of Sb 2 S 5 should give '028 gram. These 
determinations show conclusively that what remains 
after treating the samples with solution of cream of 
tartar, and afterwards with bisulphide of carbon, is 
tersulphide of antimony. It does not follow, how¬ 
ever, that No. 1 and No. la contain any tersul¬ 
phide of antimony at all. On the contrary, I do 
not believe that they contain a particle of the lat¬ 
ter salt, whilst the B.P. product contains above 90 
per cent, of it. My reasons for this belief are as 
follows :—No. 1 and No. la, together with No. 3, are 
amorphous and uniform throughout, and must have 
been prepared by the well-known process which con¬ 
sists in the addition of excess of sulphur to the soda 
solution of black antimony whilst still boiling. Sul- 
phantimonate of sodium, a sulphide of sodium, (Na 2 
S Bf ) and hyposulphite of sodium, are formed. The 
first-mentioned salt on decomposition with sulphuric 
acid yields Sb 2 S 5 , and sulphate of sodium, whilst 
H 2 S escapes. 
Sb 2 S 3 + a 2 + 3Na 2 S = 2 Na 3 Sb S 4 
Sulphantimonate of 
Sodium. 
2 Na 3 SbS 4 +3 H 2 S0 4 = Sb 2 S 5 +3 Na 2 S0 4 +3 H 2 S 
Sulphur is precipitated along with the pentasul- 
pliide of antimony, by the action of the acid on 
hyposulphite and the sulphide of sodium which are 
formed during the boiling. 
2 Na 2 S 5 +Na 2 S 2 0 3 +3H 2 S0 4 = 
3Na 2 S0 4 +3H 2 0+6 S 2 
It is thus that the excess of sulphur over that re¬ 
quired to form pentasulpliide of antimony finds its 
way into the product. 
If any confirmation of the belief that antimony 
exists in these bodies as pentasulphidepmly, were 
required, it is found in the fact that the residue of 
the successive action of solution of cream of tartar, 
and of bisulphide of carbon, which has been shown 
to be tersulphide of antimony, gives no vapour of 
water when heated in a long narrow dry tube. For 
tersulphide of antimony obtained as such by precipi¬ 
tation from a solution, after drying at 212° F., still 
contains 2 per cent, of water (Fresenius). As would 
be expected, then, the residue of the B.P. product, 
treated as above, gives off water on heating. 
The cream of tartar used in the above experi¬ 
ments was obtained by filtering a saturated Solution 
of carbonate of potassium into solution of tartaric 
acid, and washing the precipitate two or three times 
with cold water. 
Bisulphide of carbon, as met with in commerce, 
always leaves a slight residue on evaporation. . A 
measured quantity of the same sample of bisulphide 
was used in all the estimations, and the amount of 
non-volatile matter due to this was deducted from 
the total residue. 
The action of bisulphide of carbon on pentasul- 
phide of antimony, in separating two atoms of sul¬ 
phur from the rest of the compound, is very interest¬ 
ing, showing, as it does, that these two atoms are not 
so intimately combined with the antimony as are the 
remaining three. It also adds another to the many 
points of resemblance which already exist between 
the compounds of antimony and those ot arsenicum. 
From the appearance of No. 2,1 believe it to be a 
