572 Dr. Schafhaeutl on the Different Species of 
tion of the blast furnaces under some circumstances, which 
I shall further explain; so that I witnessed for months a dif- 
ferent working of the blast furnaces, even at different periods 
of the day. 
Notwithstanding the profusion of rich ores throughout 
France, it is infinitely more difficult to produce iron of good 
quality from them, than from the clay ironstone in England ; 
and excepting where iron is melted down with charcoal, the 
iron produced is of very inferior quality compared with that 
of England. 
As I think it will be very instructive to examine the chemi- 
cal properties of several specimens of such cast iron, obtained 
from the same ore and in the same furnace, I shall briefly 
describe five specimens of iron from the furnace of Alais. 
I call the first {a ) ; it has a dead gray appearance, but is in- 
tersected by somewhat whitish shining rays having a distant re- 
semblance to the lamellar crystallization of white crystallized 
charcoal iron. It was rather hard and brittle, and its specific 
gravity was 7*442. The second specimen (5) was obtained 
under peculiar circumstances. During one cast, in particular, 
the iron ran from the hearth into the moulds in the sand, and 
the rapid contraction of the exterior of those pigs forced out 
the still liquid interior through the face of the pigs like a 
fountain. The iron thus forced out is the specimen (5) ; it 
had a silvery white appearance, broke with large crystalline 
planes, approaching somewhat to a cubical fracture, and had 
a specific gravity of 7*33. 
The specimen (c) was also perfectly silver-white, consisting 
of an extremely large pearl-like granulation, easily to be 
broken, and its specific gravity was 7*582. 
Specimen {d) was extremely difficult of fusion, scarcely to be 
melted down in the fineries, and not at all available in the 
puddling furnaces ; its specific gravity was 7*61. 
Specimen (e) is a malleable iron produced from gray cast 
iron, obtained only from a few casts during the beginning of the 
working of the blast furnace. Its qualities we shall afterwards 
describe. 
On treating the specimen {a) with hydrochloric acid in the 
way before described, I observed, that during the last wash- 
ing of the sulphuret of lead v/ith boiling-hot distilled w'a- 
ter, acidulated with hydrochloric acid, as soon as this water 
dropt beneath into the solution of nitrate of lead, the surface 
of the liquid assumed a beautiful bright verrnilion-red colour 
during the formation of chloride of lead. As soon as a consi- 
derable quantity of the coloured fluid was collected, I decanted 
it into another glass and found next day that the colouring 
