( 289 ) 
cooling the tubes no crystallisation of sulphur took place. In the 
case of a mixture of 2 grams of sulphur and 10 grams of toluene, this 
lasted 10 days; in the interval the tubes were repeatedly opened to 
allow the accumulated hydrogen sulphide to escape. The product 
obtained was freed from undecomposed toluene by distillation; a 
preliminary investigation of the residual mass showed with certainty 
the presence of stilbene, thionessal and probably also of tolallyl 
sulphide. As moreover the contents of the tube had a strong odour 
of mercaptane it was supposed that the action had taken place in 
one of the following ways. Firstly, benzyl sulphydrate might have 
been formed by a direct addition of sulphur according to the equation : 
C, H, CH, +S —C, H, CH, SH 
and this on losing hydrogen sulphide according to the equation: 
2 C, H‚ CH, SH — (C, H‚ CH,),$-+H,8 
might have yielded benzyl sulphide, which according to Forst ') may 
yield as final products stilbene, totally] sulphide and thionessal. 
Secondly, the sulphur, according to the equation: 
Ge CH, Fis C,H, CSH Hes 
might have yielded thiobenzaldehyde or rather (C, H‚ CS H)x, which?) 
according to the equation : 
2C,H. CSH=>C.H,,+28 
might have formed stilbene, which then might have formed thionessal 
according to the equation : 
20.) He SS =O Hs os HS: 
In order to test the accuracy of these theories 4 grams of sulphur 
were boiled in a reflux apparatus with 150 ce. of toluene for 120 
hours, care being taken that any hydrogen sulphide which might 
have been formed and the non-condensed benzylsulphydrate were carried 
off by means of a current of carbon dioxide and passed through an 
aleoholie solution of lead acetate. Although perceptible quantities of 
lead sulphide were precipitated during that time not a trace of the 
well-known yellow lead mereaptide was found. Both the toluene 
solution and the crystalline mass obtained therefrom were carefully 
tested for the presence of benzyl sulphydrate and also of thiobenzal- 
dehyde but notwithsfanding the delicate tests for these substances 
their presence could not be demonstrated. But from the toluene 
solution we succeeded in isolating stilbene melting at 124° and from 
this was prepared the characteristic dibromide (m. p. 285—236°) by 
1) Liepie’s Annalen, Band 178. P. 370. 
*) Baumann & Krerrt. Ber. D. Chem. Ges. Band 24, P. 3307. 
