. 
* 
On the Nitrates of Iron. 33 
liquid that, though containing only 3-4 p. c. of oxyd of iron, two * 
rops imparted. a perceptible tinge to a pint of distilled water. 
In trying the reactions of various subtances with it, all the iron 
appeared to be immediately thrown down by muriate of ammonia, 
chlorid of sodium, iodid of potassium, chlorate of potash, sul- 
phates of soda, lime, zine and copper, nitrates of potash and soda, 
and the acetates of baryta and zinc. Precipitates formed more 
slowly with the nitrates of ammonia, magnesia, baryta and lead. 
Tartrate of soda furnished a precipitate soluble in ammonia. 
Ferrocyanid of potassium gave a dark peat-brown precipitate 
without the least tinge of blue. Ferrocyanid of potassium gave 
likewise a rich peat-brown precipitate. Tincture of galls afford- 
ed dark brown flocks, and on standing some time, the supernatant 
liquor turned black. Alcohol, acetate of lead, acetate of coprer, 
cyanid of mercury, nitrate of silver, and arsenious acid caused no 
change. 
With the tribasic nitrate, muriate of ammonia, chlorid of sodium 
and nitrate of soda produ ced no effect ; while the sulphates threw 
down all the iron, prussiate of potash struck a blue color, and 
tincture of galls gave a black. 
Nitrate of Alumina.—Nitrate of alumina crystallizes from a 
concentrated and somewhat acid solution, in colorless oblique 
rhombic prisms, whose height i is generally small in proportion to 
their width. They are deliquescent, and very soluble both in 
water and in nitric acid. The crystals, like those of the other 
sesquinitrates, can be best dried by spreading them on an absorb- 
ent surface, and placing the whole under a bell glass, along with 
a shallow vessel containing on acid. 
The salt was found to melt at 163° F., into a clear colorless 
liquid, which began to ccyatal when eooled down to poet 
the thermometer rapidly rising, at the same time, to 102°. 
melted mass parts with its acid much less rapidly than the tee 
of iron. One ounce of the powdered salt mixed with one-half 
ounce of inceieinate of ammonia, lowered the thermometer from 
51° to - 
100 vt pretty dry crystals, yielded by ignition 13-7 grs. of 
ainiices Distillation with sulphuric acid gave 42 p. c. of nitrie 
acid, and by boiling with carbopate of baryta, 42:42 p. c. was 
separated. The numbers corresponding to N, Al+18H, would 
be in 100 parts :—nitric acid 43-17, alumina 13-68, water 43-25. 
Nitrate of alumina appears to form with the hydrate, a series 
of salts similar to the basic nitrates of iron. But they have not 
as yet been fully examined. 
Nitrate of Chrome.—Nitrate of chrome crystallizes with diffi- 
culty in warm weather, but I have succeeded in obtaining two 
crops, one of them presenting the form of the wae rhombic 
Seconp Serres, Vol. Ix, No. 25.—Jan., 1850. 
