SOURCE, ETC., OF VOLCANIC AMMONIA. 
103 
The temperature at which all the specific gravities were taken was 15-5 C. 
(60° Fahr.). This is, of course, an important point in using the table, as the 
volume of liquid varies considerably according to the temperature ; and as at 
different heights of the thermometer comparison of volumes no longer holds 
good, consequently comparison of percentages would be equally fallacious. 
Very little more remains to be said, as this is not a comprehensive subject 
which requires much dwelling upon. I might add that the acid used was pre¬ 
pared from common phosphorus in the ordinary manner ; but I have since 
made several samples of acid from amorphous phosphorus as first mentioned by 
Mr. Groves, and decidedly prefer this latter method; the phosphorus is readily 
acted upon, entails no danger in the process, and a product is obtained in a few 
hours which ordinarily would take as many days. One little objection 
appeared, which is apt to make one think that the product is not absolutely 
pure, viz. that in the concentrated state it was more or less coloured, possessing 
a brownish or yellow tint; this might have arisen from the particular speci¬ 
men of amorphous phosphorus operated on : probably another sample would 
not show this defect. 
Lastly, I think I have shown, as far as practicable, the corrections of the 
table in question ; and I know this, that in quantitative analysis generally, and 
more especially when work is published for the use or guidance of others, as in 
the present instance, it behoves me to accept only thoroughly-substantiated and 
verified results, else an incorrect analysis, while it brings one’s own name into 
disrepute, at the same time misleads and falsifies the labours of others. It only 
remains now to be seen whether the table prove in practice as useful as it was 
anticipated to be. 4 
Baker Street, Portman Square, IV. 
Mr. T. B. Groves said that he had also found a trace of colour in the acid made 
from amorphous phosphorus, hut it was easily removed by animal charcoal. 
Dr. Parkinson said that he must reiterate an objection to the test given by the Br. 
Ph., since, if any phosphate of ammonia were present in the acid, this test would 
record the phosphoric acid of that salt as being free and available. 
Dr. Attfield bore a warm testimony to the valuable character of the table of phos¬ 
phoric acid densities presented with this paper, which he said would at once rank with the 
analogous tables of the density of other acids drawn up by Fownes, Ure, Mohr, and others, 
and which were reprinted in standard works on chemistry edition after edition. It was 
peculiarly gratifying to him that this sound and laborious work had been done by the 
first Senior Bell Scholar elected, and it was a proof that those who instituted this scho¬ 
larship for the encouragement of high aims amongst pharmaceutical students had exer¬ 
cised a most judicious liberality. He could testify to the great care and assiduity with 
which Mr. Watts had daily for some months pursued the subject. 
WHAT AEE 
TERISTICS 
THE SOURCE, 
OF THE SO-C 
ANNUAL YIELD, AND CHAEAC- 
ALLED VOLCANIC AMMONIA? 
BY MR. W. D. HOWARD. 
There is no difficulty in giving the requested information as to the source 
and characteristics of the ammonia; the annual yield is not so easily arrived at. 
However, whatever information I can give is very much at the service of the 
Pharmaceutical Conference. 
To begin, then, with the source. Almost any chemical handbook will show 
that the proprietor of those marvellous geological riddles, the boracic acid la¬ 
goons of Tuscany, does not succeed in preparing from the waters of the lagoons 
