[ 105 ] 
X. 
NOTE ON THE SUBLIMATION OF SULPHUR AT 
ORDINARY TEMPERATURES. 
By RICHARD J. MOSS, F.LC., F.C.S. 
[Prats V.] 
{Read, January 16; Received for Publication, January 19; Published, June 9, 1906. ] 
It is well known that sulphur evolves vapour at ordinary tempera- 
tures, though nobody has succeeded in measuring the tension of the 
vapour. In a paper entitled “‘ Chemical Action between Solids,” ? 
W. Hallock refers to an experiment of W. Spring, showing that 
copper sulphide may be produced by simple contact of copper and 
sulphur; and points out that. contact is not necessary, as the 
vapour of sulphur acts upon the copper. As proof of this he 
states: ‘I have made the sulphide at ordinary temperatures with 
the two an inch apart, and a wad of cotton in the tube between 
them.” Other similar proofs of the formation of vapour at ordinary 
temperatures might be mentioned ; but so far as I can ascertain the 
actual formation of crystals by sublimation at ordinary tempera- 
tures has not been recorded. The following experiment may 
therefore be of interest. 
Twenty-five years ago I placed some fragments of ordinary 
stick-sulphur in a thin glass tube 14 cm. in length, and 14 cm. in 
diameter. The tube was then exhausted by means of a Sprengel 
pump, sealed, and placed in adrawer in a horizontal position. 
I examined the tube with a pocket-lens from time to time ; but not 
until nearly twenty years had elapsed did I detect any sublimate. 
When I first observed a very minute crystal, I hung the tube upon 
a wall, opposite a window facing due east, taking care to place the 
side of the tube with the crystal on it furthest from the wall. For 
the past five years I have examined the tube frequently, and 
observed the growth of crystals. The whole of one side of the 
1The American Journal of Science, [3], vol. xxxvii., 1889, p. 405. 
SCIENT. PROC. R.D.S., VOL, XI., NO. X. O 
