i q 6 Mr. Hatchett's Analysis of the earthy Substance 
substance, even when distilled to dryness ; but, from the pre- 
ceding experiments, I had reason to believe that the aluminous 
earth and iron would be separated by reiterated distillation; I 
therefore repeated the analysis in the following manner. 
'228 $~7 / 
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4 
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4k-'*P ¥■■■ "*‘- J Jr « 
'0917/ P 
Second Analysis of the Sydneia, No. 2. 
A. 100 grains of the earth were put into a glass retort, upon 
which 400 grains of pure concentrated sulphuric acid were 
poured. The retort was placed in a small reverberatory, and 
the fire was continued till a dry mass remained. 400 grains 
of the acid were again poured in, and distilled as before. Upon 
the dry mass, boiling water was poured, and the whole was 
then emptied on a filter, and edulcorated. The residuum, after 
a red heat, weighed 87.75 grains, and consisted of siliceous 
earth, mixed with some mica, and with particles of plumbago. 
B. The filtrated solution, by ammoniac, afforded a precipi- 
tate, which weighed 9.50 grains ; and, being examined, as in the 
former experiment, yielded 6.50 grains of alumine, and 3 grains 
of oxide of iron. 
The plumbago was separated from the siliceous matter, in 
the manner already described, and amounted to about 10 grains. 
By this analysis I obtained. 
grains. 
Silica and mica 
77-75 
V/ 7 ' 7 / 
Alumine - - - 
6.50 
W4 8 & 
Oxide of iron - 
3 
'Od£BS' 
Plumbago - - - - 
10 
97- 2 5 
1 1) »■> oy || 
It appears therefore that the Sydneian earth, when treated 
with sulphuric acid, is capable of being for the greater part 
