94 C. M. Warren on the Volatile Hydrocarbons. 
also omitted to analyze and determine the vapor density of any 
one of these substances, he having added, therefore, nothing 
more than a confirmation of the results of Mansfield. He gives 
the boiling-point of benzole at 80°, of toluole at 109°, and of the 
so-called cumole at 189°-140°, which will be found to agree very 
nearly with my own determinations. Church,’ in the following 
year, published a paper on the “Determination of Boiling- 
ints” in the “ Benzole Series.” I cannot better present his 
results than by quoting the following table :— 
Boiling-point. Difference. 
°. 
. 0 0. 
Toluole, ae = C, 4(C, n°) MIME prin pau 
Xylole, C,.-H; = °C, 5(Cs H3) 126°-2 soidig 
Cnmole, Cy H1,= C5 6(C,H,) — aerah 2202 
Cymole, Ces Hi y= Cet (C, H,) 170°-7 
J 
thus giving room for a middle member between them, and pre- 
serving a remarkable uniformity of difference—viz. 22° and a 
That the earlier investigators had found in coal-tar naphtha 
only the two lower members (C,,H, and C,,H,) and the two 
¢ p . The ‘al 
discovery of this body in coal-naphtha by Church, together with 
tile than benzole is by no means composed of a single substance, Hayine had @ 
large quantity of this volatile material at my command, I have esi able | ra obtain 
the separate apparently in a state of great purity. Of the two bodies 
one of them boils constant at about 40°, and the other near 0°. Both are 
compounds containing sulphur, and therefore will more properly form the subject 
of a separate paper. i 
* Philosophical Magazine, 1855, [4], ix, 256, 
