262 Scientifie Intelligence. 
The following experiment proved that these last named gases are in- 
compatible. jar filled with deutoxyd of nitrogen and sulphuretted 
hydrogen, shewed no action ; a few bubbles of oxygen colored the gases, 
caused sulphur to deposit, and the color rdisappeared. Each addition of 
oxygen produced the same effects, uatil all the sulphuretted hydrogen 
was removed. 
Upon this reaction the author bases his process for obtaining sulphur 
from autpbite of lime. The sulphate is to be decomposed with coal, 
and the moist sulphuret by the carbonic acid from a furnace. The sul- 
ahaysted hydrogen given off, is to be conducted into a chamber con- 
tuining air and deutoxyd of nitrogen; which last will, in small quan- 
tity, suffice as in the manufacture “of sulphurie acid, for the preparation 
of large quantities of product. In this case water is formed, and sul- 
phur deposite d. 
The nitric acid which had been acted upon by sulphuretted hydro- 
gen in the above experiment, contained sulphate of ammonia, with 
scarcely a trace of nitrate. G, ¢. achiever 
8. New and Economical Preparation of the Chromates ; 
Jacquetatn, (Comptes Rendus, Oct., 1847.)—An intimate mixture © of 
nely pulverized chalk and chrome ore, is to be exposed in thin layers 
in a reverberatory furnace, to a red heat for nine or ten hours, stirring 
ten or twelve times with a rake. 
The tests of the perfect conversion of the oxyd into chromate are, 
the ee a oe color of the mass and its perfect solubility in hy- 
drochloric 
mass vii ground in a mill, is mixed with hot water, constantly 
agitated, and sulphuric acid added to slight acid reaction. ‘The ch 
mate of lime is thus changed to bichromate ; some pulverized cha lk is 
then gradually added, to remove peroxyd of iron, and the liquid after 
standing to clear is decanted. 
a chromules of at and zine may now be prepared at once, the 
sdiaciadiaiate transformation into bichromate of potash being economi- 
cally avoided. his latter salt may however be readily prepared from 
the liquid, and quite pure, by solution of carbonate of potash, which 
produces insuluble carbonate of lime and solution of bichromate of 
potash, 
The chromate of lime, with excess of base, has the green color of 
oxyd of chrome, and as it is nearly insoluble in water, bas probably 
led to the belief that no chromate was formed. 5. 
9. Preparation of Chlorie Acid and the Chlorates; by Lew 18 
THompson, (Phil. Mag., December, 1847 Supple. )—Dissolve in the 
least possible quantity of boiling water éaliinalonus (122-81) of re 
of potash and (168°34) of biturtrate of u mmonia. Mix the solutio 
and let the bitartrate of potash crystallize out. Mix the clear ue . 
tion with an equal bulk of alcohol, and filter, Boil the alcoholic solu- 
tion of chlorate of ammonia in a narrow necked vessel with exeess © 
resh carbonate of payee until the ammonia is expelled ; filter, evapo 
rate, and erystalliz 
The chlorates of strantian and lime are prepared in the same Ways 
the metallic chlorates by double decomposition from chlorate of baryta- 
