24 Improvements in Physical Science (Jan. 
may be distilled over. The same acid may be formed artificially by 
exposing deuto-chlorous oxide to the action of voltaic electricity in 
an apparatus constructed with platinum wires. According to the 
analysis of Count von Stadion, when this salt is exposed to heat it 
is converted into 
Potaswen ek Tk Es Bae YB 
Chlomiée or. Us: ee iaate wet 2559 y 3408 
ORyrew Ne is. cadets Poems cies a 
Now 2°849 grains of potassium require, in order to be converted 
into potash, 0°5819 grain of oxygen. There remain 4°01 grains. 
Hence the acid must be composed of 
Chhborine 0.6 facie id stag ote be ine eo eae 
Oxygen. i046 o08 SU ea RS os 401 
But these two numbers are to each other very nearly as 4°5 (an 
atom of chlorine) to 7 (7 atoms of oxygen). Hence it follows that 
this acid is composed of one atom of chlorine and seven atoms of 
oxygen. Count von Stadion calls it oxy-chloric acid, It may 
perhaps be better to give it the name of perchloric acid. Thus it 
appears that no fewer than four combinations of chlorine and 
oxygen exist, namely, 
Chlorine. Oxygen. 
Proto-chlorous oxide, composed of 1 atom + 1 atom 
Deuto-chlorous oxide .......... 1 + 3? 
Chior ie Ci oc uo a'erate, ts a aia 2 + 5 
Perchlasie eid: jis. sae aniasie v0 1 + 7 
So that an uneven number of atoms of oxygen, it would appear, 
always unite with an atom of chlorine. 
IX. SIMPLE COMBUSTIBLES. 
1, Boron.—The present method of preparing boron is both ex- 
pensive and troublesome. Dobereiner has proposed atiother, which 
is at least cheaper. (Schweigger’s Journal, xvi. 116.) Borax is 
fused, reduced to a fine powder, and mixed with the tenth part of 
its weight of lamp-black. ‘The mixture is put into a gun-barrel, 
and exposed for two hours toa white heat. Abundance of carbonic 
oxide is driven off, indicating a decomposition of the boracic acid. 
After the process, a compact mass remains, of a greyish-black 
colour. This mass, being pounded, and repeatedly washed with 
hot water, and finally with muriatic acid, leaves a pulverulent sub- 
stance, of a greenish-black colour, which possesses the properties of 
boron, excepting that it is mixed with a little charcoal. 
Leopold Gmelin has made some attempts to combine boron with 
iron. A mixture of 10 parts iron filings and one part boracic acid 
was exposed in a Hessian crucible to the violent heat of an iron 
furnace. A metallic mass was obtained, which had obviously been 
fused. It possessed some ductility, was of a silver-white colour, 
