320 
METHOD OF KEEPING SYRUPUS FERRI IODIDI. 
following day the etherial solution, which was lemon-coloured, was evaporated, and the 
residue dried at 212° F. Its amount was 0 931 gramme; this root bark contains, 
therefore, 4-774 per cent, of alkaloid soluble in ether. I obtained from these 0 931 
gramme beautiful herapathite, but found, in the meantime, that the largest part of this 
alkaloid soluble in ether is not quinine , but an amorphous alkaloid. I am still occupied 
with researches to find out the real nature of this amorphous alkaloid. . . . The re¬ 
maining alkaloids, which were not dissolved by ether, proved to be cinchonine , with only 
a trace of cinchonidine. In this root, like in the former, I found the cinchonine parti- 
ticularly fit to crystallize, and consequently I obtained beautiful sulphate of cinchonine 
from it. 
J. E. Howard, Esq., to C. R. Markham , Esq. 
For the guidance of the Indian Government I send the foregoing interesting and well 
executed analysis, and add that it accords most nearly with the previous analyses by 
Dr. de Vrij and myself of No. 2 of Root Bark of larger size, but of the same parcel, and 
that these specimens of root bark would command but a low price in the London 
market from the causes before stated. I do not think the root bark of this species would 
repay .cultivation. 
ON THE TRUE METHOD OE KEEPING THE SYRUPUS 
EERRI IODIDI EREE EROM CHANGES. 
TO THE EDITORS OF THE PHARMACEUTICAL JOURNAL. 
Sirs,—Recent experiments on the syrupus ferri iodidi have led me to the 
conclusion that this syrup can be made to keep for any length of time with¬ 
out undergoing its usual changes. A large quantity of this syrup, made 
strictly according to the British Pharmacopoeia, now over two months, is at 
this moment as perfectly colourless as the day it was made. 
Three ounces of syrup were divided between three one ounce-phials ; one 
corked, one stoppered, and the other, mouth well capped over with two folds 
of thick vegetable parchment, previously moistened in water. The corked 
phial with contents was then placed in a cold dark corner in the cellar,—the 
usual place for keeping this syrup. The stoppered one, with contents, was 
next placed into a small jar, half tilled with cold water; and that capped over 
with vegetable parchment was kept in a warm position in the shop, alongside 
the mother syrup. Two weeks lapsed away, and they were examined. The 
syrup in the corked phial assumed a dark brown colour, which was formed 
nearest the cork and gradually descended. The cork exhibited the usual re¬ 
sult,—a blackish colour,—produced by the action of the iron on the tannin na¬ 
turally existing in corks. The syrup in the stoppered phial had undergone 
a more rapid and complete change of colour ; but not to any degree as dark 
as that just described. It indicated more of the pure oxide of iron in solution. 
On the application of heat (the phial being placed in a water-bath) the syrup 
was again rendered colourless ; whilst, on the other hand, that capped over 
with vegetable parchment, in the manner described, now remains, with the 
mother syrup similarly treated, perfectly colourless, and there is not the 
slightest indication of its ever changing. 
From these results not the slightest doubt can exist on the fact that as the 
agency of heat is required to effect the quasi-chemicsil combination of iron and 
iodine, it follows, therefore, that to keep this compound stable, the syrup 
should always be kept in very warm position. The prejudicial use of corks 
should be entirely dispensed with. Stoppered bottles may be used with ad¬ 
vantage ; but the subsequent crystallization of the sugar around the stoppers 
renders them objectionable. Thick vegetable parchment I found answered 
