310 Mr Grauam on Water as a Constituent of Salts. 
it is attempted to form it by double decomposition from the bi- 
sulphate of soda, in general a large quantity of sulphate of soda 
and of sulphate of copper are separately deposited before the 
double salt appears. It is then deposited in a crust, consisting 
of small but distinct crystals, which are slightly deliquescent, and 
appear to contain two proportions of water. This salt is easily 
made anhydrous, and thereafter fuses at an incipient red heat 
without loss of acid, and remains of a blue colour when cool. 
The fused salt does not split into thin scales in the progress of 
cooling, as the corresponding sulphate of copper and potash does. 
Sulphate of Manganese with Saline Water : MnSH+H*. Sul- 
phate of Manganese. 
The water in this salt was found to be reduced from five ato- 
mic proportions to little more than one, by drying the crystals 
in open air at 238°, while one entire atomic proportion was re- 
tained at 410°. Flesh-coloured crystals, dried in vacuo in warm 
summer weather, without artificial heat, lost somewhat more 
than three proportions of water. 
Anhydrous Anhydrous 
Salt. Sie 
Flesh-coloured crystals of salt, . . . . . 28.42 60.06 
Do. dried at 238°, . . Behe o408 21.53 13.05 
A portion of last, afterwards dried for one 
hour between 380° and 410°, . . . 9.54 11.74 
A portion of same, dried for one hour between 
415° and 468°, [Sa L1G espe 10.90 | 0. 5.14 
sulphuric acid, thermometer 64° to 72°, 
Crystals dried for nine days in vacuo cet! 
but had lost nothing the last two days, 
Composition of sulphate of manganese with 
one atom of water (by theory), oe Fi ahae 
Composition of do. with five atoms of water, | .:.... oes 59.4 
A crystalline crust of sulphate of manganese, deposited from 
