32 On the Nitrates of Iron. 
* yielded 86:5 grs. of sulphate of baryta, indicatirlg 40-104 p. c. of 
dry nitric acid. Hence the formula is probably N, Fe +18H, 
which would give in 100 parts ;—nitric acid 40-095, peroxyd of 
iron 19°819, water 40-086. 
Basic nitrates —A liquid is used in cotton dyeing, which is 
prepared by adding iron turnings to pe till the solution 
assumes a very dark red color. A fair sample of this solution, of 
sp. gr. 1-478, was found by analysis to contain five equivalents of 
nitric acid to two equivalents of sesquioxyd of iron, A portion 
of the same placed in contact with metallic iron, remained clear 
until nearly enough iron had been taken up to form a sesquibasic 
nitrate, ( N, Fe ,) when a —, precipitate began to appear, whose 
exact nature it is difficult t 
A full sesquibasic idtvaner was formed by adding crystals of the 
nitrate to the proper quantity of freshly precipitated oxyd of iron. 
And proceeding by the same means, but with slow and cautions 
steps, as into an unknown region, I was successively astonished by 
the discovery of soluble basic nitrates containing to three equiva- 
lents of acid, two, three, six, eight, twelve, fifteen, eighteen and 
pees on equivalents of base, respectively and then, from the 
ith which the union took place in the last, I suppose 
ants limit Riche: Yet this liquid was found to bear the addition 
of a small quantity of lime water, without change. 
On arriving at these remarkable results, the question naturally 
came up, whether there were any chances of error. But on ex- 
amination, no foreign substance was detected, and the analyses of 
the six, twelve, fifteen, and twenty-four bagic compounds, agreed 
so nearly with the syntheses as to remove all doubts 
ich of these bodies have claims to be reg arded as true 
titi compounds, there seems to be no clue but fansioay to de- 
termine. hey all form intensely deep red liquids, which are 
not altered by dilution, nor by brisk boiling, provided the evapo- 
ration be not carried too far. By spontaneous evaporation they 
leave a very dark red powder, perfectly soluble in water. That 
left by the dodecabasic nitrate, was not deliqnescent, and lost 
30 p. c. of its weight by ignition. Hence its empirical composi- 
tion would be N Fe, +9H. 
When cotton cloth is dipped in any of ides solutions, and 
dried, the oxyd of iron becomes permanently attached. Indeed 
the adhesion of the base to cotton fibre, renders filtration through 
paper exceedingly slow 
Since spring and river water, and the solutions of most salts, 
are rar with the twenty-four basic nitrate, it was found 
necessary to use an abundance of distilled water for washing the 
oxyd used in its preparation. So intense was the color of this 
