3 
Ordinary Meeting, October 17th, 1871. 
Rev. William Gaskell, M.A., Vice-President, in the Chair. 
“ On the Oxychlorides of Antimony,” by Mr. William 
Carleton Williams, Student in the Laboratory of Owens 
College, communicated by Professor H. E. Roscoe, F.R.S. 
Phosphorus Oxychloride PO Cl 3 having been prepared by 
heating together one molecule of phosphorus pentoxide with 
three of pentachloride, it appeared not unlikely that a simi- 
lar reaction might occur with antimony giving rise to the 
missing oxychloride corresponding to the phosphorus 
compound above mentioned. 
The following investigation was undertaken at Dr. 
Roscoe’s request with the view of elucidating the above re- 
action as no oxychlorides derived from the pentachloride 
have as yet been described. 
A mixture of one molecule of antimony pentoxide pre- 
pared by heating the pentachloride with water with three 
molecules of the pentachloride was heated for some hours 
in sealed tubes to 140° C. On opening the tube after cooling 
it was found to contain, besides unchanged pentachloride and 
pentoxide, two distinct solid crystalline compounds. When 
the pentoxide prepared by the action of nitric acid on the 
metal is heated with the pentachloride in a similar way no 
oxychloride is formed. 
One of these fuses at 85° C. to a clear yellowish liquid, 
whilst the other, produced only in small quantities, is 
found adhering to the top of the tube in minute yellow- 
ish crystals, which fuse at a higher temperature. In 
order to obtain the first of these substances in a pure 
state it is sufficient to place the tube upright in a vessel of 
water at 90° with the empty end downwards ; the fusible 
oxychloride then melts and collects as a perfectly clear 
yellowish liquid. After cooling, the tube is opened and the 
