740 
ME. C. GEEVILLE WILLIAMS OX SO^LE OE THE PEODUCTS 
•2872 gramme of substance gave *1447 of carbonate of lime. 
Experiment. 
Calculation. 
Bromine . 
. . 79-85 
Br 80 
Calcium . 
. . 20-15 
Ca 20 
100-00 
100 
The ignited salt, on being moistened with warm water, became extremely hot. and 
hissed like hot metal when quenched. 
The preceding salt being deliquescent, and consequently not convenient for analysis. 
I digested a fresh portion of the acid upon carbonate of baryta, the latter being in 
excess; the solution was boiled, filtered and evaporated to drj-ness on the water-bath. 
After two hours’ desiccation at 100°, it gave on a determination of the barium 43'67 per 
cent., corresponding to the formula BaBr, HO; requii’ing 43-53. By ignition the per- 
centage of barium was raised to 46-8. BaBr requires 46-16. Dui-ing ignition the salt 
became grey, but regained its original appearance when moistened with water. 
A determination of the per-centage of dry hydrobromic acid in the fluid was next made. 
I. 2-0624 grammes of acid gave 1-7782 of bromide of silver. 
II. 1-1190 gramme of acid gave -9720 bromide of silver. 
Or, per cent. — i. II. 
37-2 36-96 
The specific gravity of the fluid obtained in this singular manner was 1-320 at 18°. 
The small quantity of fumes evolved during the distillation points to the existence of a 
definite hydrate; HBr-j-15HO would contain 37-5 of hydi-obromic acid, a number not 
far from that found by experiment. The reason for examining thus minutely the lower 
layer of liquid, was to trace the nature of the reaction resulting in the production of the 
oxidized fluid. It is plain that water was decomposed by the excess of bromine ; the 
oxidation therefore resembled that produced by the halogens generally. 
The examination of the bromine compounds was not piu’sued fiu-ther because their 
products of decomposition appeared more interesting. 
The results detailed render it evident that the only method of stud)ing satisfactorily 
the C” H" group as it existed in the oily fluid would be by means of its derivatives. It 
is well known that bodies of this class must, after the action of alcoholic potash, be 
regarded as bearing the same relation to the negative that the hydriodic ethers do to the 
positive radicals. Like them, the halogen compounds, when decomposed by metals, jield 
hydrocarbons, having, for four volumes of vapom-, double the number of atoms of cai-bon 
and hydrogen existing in the iodides, bromides, &c., and these hydrocarbons or radicals, 
as they are still called, have consequently a higher boiling-point than if the number of 
carbon and hydrogen atoms remained the same. Thus propylene, C® H®, is a gas, while 
allyle, the negative radical, is a fluid boihng at 59°. It was therefore probable 
that the hydrocarbon, C'^ would, by treatment of the bromine compound until sodium, 
yield a derivative boiling at about 116°. 
For the purpose of acting on the bromine compound with sodium, a small glass retort 
