478 
SECOND REPORT—1833. 
of aqueous vapour, cautiously regulating the heat so as not 
to fuse the metal, M. Haldat * has obtained crystals of oxide 
of zinc, of a honey colour, almost transparent, and of a rhom- 
boidal form.—By a similar process he has obtained minute 
groups of brilliant rhombohedral crystals of specular iron, 
equal in lustre and in play of colours to the freshest specimens 
from Elba or Framont. 
Schindler f has also shown that a hydrated oxide of zinc may 
be obtained in crystals by uniting a rod of zinc and iron, and 
placing them in caustic ammonia in a close vessel. Gas is de¬ 
veloped, and in a few days the inside of the vessel is covered 
with small transparent crystals, which are permanent in the air, 
• • 
and consist of oxide of zinc 81*63, water 18*36=Zn +H. 
Iron, carburets of. —MM. Gay-Lussac and Wilson J have 
published the results of a series of analyses of carbonaceous 
irons, which show the carbon in the bar irons examined to 
vary from fourteen to twenty-nine, and in the steels from 
sixty-two to ninety-three ten-thousand parts. In gray cast- 
iron it varied from sixteen to twenty-eight, and in wdiite from 
twenty-three to twenty-seven thousand parts. It would be de¬ 
sirable to know how the carbon was determined, as they make 
it so much less than former experimenters. 
Lead, sulpliurets o/’.—Bredberg has added to our knowledge 
of the compounds of lead and sulphur by forming two new 
compounds of these elements : the lowest, 4 Pb + S, is formed 
by fusing together 35 parts of galena with 31*6 of lead: it is 
granular and sectile. The other, S +3 Pb, is obtained by fusing 
the same mixture in a crucible with borax. It is crystalline, 
lamellar, and slightly malleable. 
Super-sulphuretted. —I have lately analysed the super-sul¬ 
phuretted lead of Dufton, and found that it is merely a mixture 
of sulphur and sulphate of lead, in proportions which probably 
vary. 
Bismuth, expansion of, on becoming solid. —Marx § has esta¬ 
blished a very important fact in regard to melted bismuth. 
He finds that at the moment of solidifying it expands ^Vrd of its 
volume. He considers also that, like water, it has in the fluid 
state a point of maximum density. 
Bismuth, oxide of. —Mr. Phillips || has shown that a deep 
blueish black oxide of bismuth is sometimes obtained when the 
subchloride is decomposed by alkalies. This might be taken 
* Ann. de Chhnie , xlvi. p. 72. f Geiger’s Magazin, Aug. 1830, p. 174. 
X Journ. of Science, 1830, p. 204. § Nenes Jahrbuch, i. p.454; ii. p. 114. 
|| Phil. Mag. and Ann. of Phil. 1830, p. 410. 
