284 Scientific Intelligence. 
nitrogen, and nitrous acid vapor, the latter of which is condensed 
passing through water, while the residue in the retort consists of caustic 
soda and oxyd of zinc. Water completely separates these two, leaving 
the zinc-oxyd fit for a second operation. The soda solution serves for t 
products obtained are oxygen contaminated with variable quantities of 
by 
a 30 gallon sto 
moveable colander-like shelves, upon which are strown 48 pounds of res 
idue, the product of previous operations, and consisting of zinc-oxyd, 
caustic soda and nitrate or nitrite of soda—this caput mortum stuff 8 
moistened with five pounds of water and carefully strewn on the shelves 
(in the manner of the hydrate of lime, in the common, dry-lime purifier 
for coal gas). The purifier thus furnished is closed by a lid of stone 
each charge of 50 pounds, 94 hours. Campbell finds the proporte! 
nitrogen is diminished by using a moderate temperature and al 
of water in the purifier. This water becomes very acid from the 
and NO, absorbed, these products resulting of course from the react 
of the materials. 
The cost of oxygen by this process is less than from any other 
proposed as will appear from the following comparison, based 08 ©” 
ville’s and Debray’s well known statements.’ 
1 cubie meter (= 35°317 cubic feet), rs. 
“ oe 10 
s. d. English currency: 
from chlorate potassa, 4 “8 
— 
“ 
oe x. manganese, 487—4 0% e e 
" « HO, SO, by heat, Iv <==0 10 " . 
“ “« — "Webster’s NaONO,+-Zn0, 74 “ “ 
Rid “Do. rejecting all products, 1 9x5 
It is plain from this statement that, without considering Mt Oe 
Webster's process is cheaper than any other: but Deville’s meth pa 
* Chem. News, vi, pp. 218, 268, See also same Journal, vi, 287 and 259, va, 
for additional information. 1 
® This Journal, [2], xxxi, 280, 427, and Ann. de Chim. et Phy., [8], lxi, 9” 
