TRANSACTIONS OF SECTION B. 967 
status nascendi in accounting for this action. It is indeed possible that the reaction 
may be a direct one. Whereas the heat of formation of water is 68,360 cal., that 
of 2HC1.Aq is 78,640 cal., nearly 10,000 calories in excess; and the reducing action 
on the indigo may be ascribed to this excess. But with our present views regard- 
ing the formule of water and hydrogen chloride, which rest so far on a physical 
proof—that of the volume proportions of the gases and their compounds, it appears 
to me that the phenomena described present corroborative evidence of a chemical 
kind of the correctness of the method of writing the equations, 
H, + Cl, = HCl + HCl, and 
2H, +O, =H,0 + H,0. 
4, On the Spontaneous Polymerisation of Volatile Hydrocarbons at the 
ordinary atmospheric temperature.' By Professor Sir Henry KH, 
Roscoz, F.R.S. 
Some time ago a small quantity of a white crystalline camphor-like substance 
was sent to me by Mr. W. W. Staveley of West Bromwich, with the information 
that it had been obtained by him from the most volatile portions of the hydro- 
carbons, resulting from the decomposition of crude phenol at a red heat. Mr, 
Staveley writes, ‘ After standing for some weeks the greater portion of the volatile 
bodies, boiling from 20° to 30°, was changed by absorption of atmospheric oxygen 
into bodies boiling between 160° and 170°. After distilling off the lighter portion 
from the oxidised mixture, the residue in the retort, on cooling, solidified to a white 
crystalline mass.’ 
Examination of this product has proved that the above supposition is incorrect, 
and that the crystalline body is a hydrocarbon having the formula C,,H,,. For 
the purpose of purification the crude material, which had a yellow colour and was 
saturated with liquid, was pressed between filter-paper, and afterwards distilled ina 
vacuum, when it came over without decomposition at about 63° under 9 m.m. of 
pressure, but is found to decompose when distilled under the ordinary pressure. 
The hydrocarbon thus purified is perfectly colourless, crystallising in brilliant 
stellar clusters which melt at 32°9°. It volatilises slowly at the ordinary tem- 
perature like camphor, crystals being deposited on the upper part of the vessel 
containing it. Analysis gave: 
1 2 3 - Mean 
Carbon, : - 90°78 90:79 90°96 90°84 
Hydrogen . - . 959 8-69 9°27 9°18 
100°37 99°48 100:23 100-02 
The vapour density by Hofmann’s method gave: 
u 2 
Weight of substance . - 0:0728 g. O:1777 g. 
Barometer reduced , ‘ - 760°7 m.m. 760°7 m.m. 
Mercurial column . : - 686:°2 m.m. 587:0 m.m. 
Volume of vapour . < se por! Ce: 206°3 c.c. 
Temperature of vapour . onyeellulos 132° 
Vapour density - “ - 4:39 4:57 
The molecular formula C,,H,, requires a vapour density of 4°57, and the percent- 
age composition C=90'°9 H=9-10. The sp. gr. of the solid hydrocarbon is 1-012 at 
17°-5,the crystals sinking under water in a vacuum. It dissolves readily in petroleum 
spirit, ether, and alcohol, and possesses a peculiar smell resembling, but distinct 
from, that of camphor. On exposure to air it rapidly absorbs oxygen and is con- 
verted into a yellow resin. When heated in a vacuous tube to 180° for four hours 
the compound undergoes further polymerisation, and an opaque white battery mass 
is obtained, the solid portions of which melt with decomposition at 200° to 220°. 
Both solid and liquid possess a very strong odour. The hydrocarbon C,,H,, at 
once combines with bromine, and yields a liquid bromide, which however soon 
1 Chem. Soc. Trans. xlvii. 669. 
