328 J. M. Ordway on Nitrates of Iron. 
equivalents of water; then add trihydrated nitric acid enough 
28.—100 g. of Fe, O,,3NO,,18HO, were gently heated till 27 p. ¢. < 
were evaporated, one-half of the water and one-eighth of the acid being 
expelled. 42g. of monohydrated nitric acid were added and the dish 
suitably covered was set out in an open shed for several days in the 
coldest weather of winter. No erystals formed except a slight fringe 
around the edge, where a little moisture had probably been absor - 
from the air. 
| ML. Sch roneous] 
in this Journal, vol. xxvii, p. 197, such a salt as Fe, O,,3N0,, 
SHO. He probably meant to refer to p. 17 of that volume, 
where I have taken the liberty of showing the generic agree- 
ment of the sesquinitrates with the sexhydrated gr betpas Be 
e 3 
had not met with Hansmann’s account of the cubic salt, an 
therefore was not aware of the peculiarity of nitrate of iron in 
ranking among the tetrahydrates as well as in the more exten- 
- Sive class of sexhydrates, Other salts of the tetrahydrate class 
Way exist _as anhydrous nitrates, and it is a question whether 
seneurer-Kestner’s more recently discovered salt, eX, Hz, 18 not 
* Bulletin Soe. Chimique de Paris, March, 1862, p. 36. 
