fects of Mercurial Vapow. 131 
carried to 22 degrees ; but in rainy, moist weather, to 18 de- 
grees only. When the water is nearly saturated, it passes 
toa large building, where are the pans for boiling, and the — 
salt is crystallized in the usual method. 
Thus, 8000 hogsheads of water, in passing through the Mai- 
sons d’Epines, are evaporated to about 550; and only one 
sixteenth part of the fuel is consumed, that would be required 
for evaporating the whole quantity of water by fire. 
The faggots are changed at periods of from four to seven 
years. Those in Nos. 1 and 2, where the saline impregna- 
tion is weak, will decay sooner than in Nos. 3 and 4. In 
No. 3 all the twigs acquire so thick a coating of selenite, 
that when broken off, they resemble stems and branches of 
encrinites. 
The Maison des Cordes was invented by an ingenious Sa- 
voyard named Buttel. The original intention of this building 
was to save the expense of fuel, by crystallizing the salt itself 
upon cords, from which it was broken off by a particular in- 
strument for the purpose. ‘This process is at present aban- 
doned for crytallizing ; but the cords are still used for evap- 
orating, and are found to answer better for the higher con- 
centration of the water than the faggots. This method did 
not answer for the first evaporation, because the water rotted 
the cords ; but the water which 1s considerably concentrated, 
deposites a coating of selenite around the cords, completely 
defending them from the action of water. The cords have 
many of them remained ia use thirty years, without being 
changed. 
The fuel used at the pans for the last process is partly 
wood, and partly anthracite from the neighbouring mountains. 
The quantity of salt made here annually is about 2,250,000 
Ibs. and of sulphate of soda about 187,000 lbs. The other 
alkaline matter which adheres to the pans is sold to the glass 
makers. The annual expense of these works is about 
100,000 francs, and the net annual profit, about 50,000 francs. 
18. Effects of Mercurial Vapour.—In the Philosophical 
Transactions for 1823, Part Il. William Burnett, M. D. 
gives a very interesting account of the effects of mercurial 
vapours on the crew of his majesty’s ship Triumph in 1810. 
The Triumph, of 74 guns, was lying in the harbeur of Ca- 
diz, in March, 1810, when a Spanish vessel laden with quick- 
sliver, was wrecked uuder the batteries of that town. The 
