SPIRITFS AMMONt.E AROMATICUS. 
377 
Of the process and preparation of the British Pharmacopoeia, Mr. Squire 
says, “ This is a great improvement on the London process ; it contains a larger 
quantity of carbonate of ammonia, and does not change in colour by keeping.” 
However, the determination of The ammonia and carbonic acid, in good spe¬ 
cimens of the two preparations, throws a different light upon their composition. 
In a fluid ounce of each, the following quantities were found;— 
P. L. B. P. 
Ammonia (NHg) 7‘48 grains . . . 10'71 grains. 
Carbonic acid . 6‘38 ,, ... 7'04 ,, 
It appears, then, that the London preparation is not a solution of the carbo¬ 
nate of ammonia, but that it contains three equivalents of ammonia to two of 
carbonic acid; or say one equivalent of ammonia to every two equivalents of 
the neutral carbonate. This is a more cogent reason than the one assigned by 
Philips for its “ greater pungency,” etc. When a spirituous solution of the mono¬ 
carbonate of ammonia is submitted to distillation, as in the process of the British 
Pharmacopoeia, nearly one-half of the carbonic acid is expelled in the early part 
of the operation, and there are found in the distillate about two equivalents of 
ammonia to one of carbonic acid. 
The aromatic spirit of ammonia of the Pharmacopoeia contains, as the above 
figures show, nearly half as much more ammonia, but only a tenth as much more 
carbonic acid as the London preparation ; and may be regarded as a solution of 
ammonia and neutral carbonate of ammonia, in equivalent proportions. 
If the framers of the process were aware of the composition of the distillate, 
it seems to me that they chose a roundabout and unphilosophical mode of effect¬ 
ing their object. 
A more direct one is the following 
Take of Carbonate of Ammonia, four ounces. 
Strong Solution of Ammonia, eight fluid ounces. 
Volatile Oil of Nutmeg, four fluid drachms. 
Distilled Oil of Lemon, six fluid drachms. 
Rectified Spirit, six pints. 
Distilled Water, eight and a half ounces. 
Powder the carbonate of ammonia, introduce it into a bottle, add the water 
•and solution of ammonia, and shake occasionally until solution is complete; then 
•add the spirit and essential oils. At first a portion of the salt is precipitated, 
but it is redissolved in a few hours if the bottle be shaken now and then. The 
solution may be cleared by subsidence, or filtered through white blotting-paper, 
with care, to avoid loss of ammonia. 
This differs from the preparation of the British Pharmacopoeia, merely in 
having a slight tinge of colour, similar to that of spirit of nitrous ether. If, be¬ 
fore adding the essential oils to the bulk of the solution, they be distilled with 
three or four ounces of it, and an ounce or two of water, that trifling difierence 
will be prevented. I look upon this, however, as a needless refinement. 
Lastly, there is an error in the Pharmacopoeia touching the strength of the 
strong solution of ammonia, which seems to have escaped notice. That solution 
is to contain 32-5 per cent, of Nllg, to be of specific gravity 0-891, and to re¬ 
quire for the neutralization of 1 fluid drachm 102 measures of the volumetric 
solution of oxalic acid. But if it had the specific gravity and saturating power 
stated, it would contain 35-5 per cent, of NHg. The fluid drachm ought not to 
require more than 93 measures of the oxalic acid solution for neutralization. 
Sheffield, October, 1866, 
Professor Redwood said he could not in one respect agree with the author of 
VOL. VIII. 2 c 
