470 DR. JOHN STENHOUSE ON THE OILS PRODUCED BY THE ACTION 
same effect is also produced when paper, white silk, linen or cotton cloth is similarly 
treated. The red colour begins to appear in the course of a few minutes and remains 
for some days, after which it changes to a brownish yellow. I regard this coloration 
as an effect of mutual oxidation, for I have failed in procuring any crystalline compound 
similar to furfuramide, either with aniline or with some others of the volatile alkaloids. 
Double Chloride of Furfurine and Platinum. 
Dr. Fownes, who first prepared this salt, states that a solution of hydrochlorate of 
furfurine, when treated with a slight excess of bichloride of platinum, forms a nearly 
insoluble bright yellow precipitate. This is true only when the double salt is produced 
by mixing cold aqueous solutions. When however chloride of platinum is poured 
into a hot solution of muriate of furfurine in weak spirits, the same salt is slowly de- 
posited on the cooling of the liquid in bright yellow needles, often an inch in length, 
and closely resembling carbazotate of potash in appearance. 
I. 0*4265 grm. salt prepared in the way just described and dried in vacuo, gave 
0*089 platinum = 20*86 per cent, platinum. 
II. 0*326 grm. salt prepared in the way just described and dried m gave 
0*0670 platinum = 20*55 per cent, platinum. 
The calculated quantity for the formula H 12 N 2 Og-t-HCl+PtCl, is 20*82 pla- 
tinum per cent. Dr. Fownes found 20*45. There can be no doubt, therefore, 
notwithstanding the difference in their mode of preparation and crystalline state, that 
both salts are identical. 
Nitrate of Furfurine. 
Dr. Fownes also analysed nitrate of furfurine crystallized from an aqueous solution. 
It then forms irregular long acicular crystals arranged in stars. From alcohol it 
is deposited in large very regular rhombic prisms, which possess great lustre, and may 
be readily obtained nearly an inch in length. If the spirituous solution out of which 
the salt has crystallized is very strong, its crystals, which are at first perfectly trans- 
parent, on being kept for some time in a dry atmosphere become quite opake, but if 
they are crystallized out of dilute spirits they retain their transparency. 
0*2905 grm. salt crystallized out of spirits and dried in vacuo, gave 0*580 carbonic 
acid and 0*109 water. 
Found numbers. 
C 54*35 54*45 
H 3*93 4*16 
The formula of this salt is Cgg Hi 2 N 2 Og-j-NOg-fHO. 
It is plain therefore that the nitrate, whether it is crystallized out of water or weak 
spirits, does not vary in composition after it has been dried in vacuo. 
