Intelligence and Miscellanies. 175 
it gave delicate and beautiful shades and exposed for weeks 
to the direct rays of a midsummer sun, it remained unchang- 
ed. These properties induce me to recommend it as an ad- 
dition to the number of pigments among which the artist 
can make a choice. 
An economical process for preparing this salt, consists in 
boiling a mixture of one hundred and twenty five parts of Io- 
dine, and two hundred and fifty parts of clean fine iron filings, 
with one thousand parts of rain water, in an oil flask. When 
the brown color of the liquid, is succeeded by a light green, the 
clear fluid is decanted and the residue washed with warm 
remote angle, if a group of crystals be the subject of exper- 
iment. This change of color is accompanied by a sensible 
