168 PROCEEDINGS OF SECTION B. 



I have shewn the very enei'getic decomposing power of metallic 

 sulphides upon certain of the soluble salts of gold and silver ; also 

 the fact that the metal reduced in this way is electro-deposited, 

 and that in a coherent form, upon the decomposing body itself. 

 From these facts I have drawn the conclusion that these metallic 

 sulphides are probably largely concerned in the production of 

 native gold. 



I have also proved that gold like the base metals is rapidly 

 aiTected, in a chemical way, by certain of the constituents of air 

 in conjunction with water, by which it becomes minutely corroded 

 and as minutely enfilmed ; and I have proved by direct experi- 

 ment and legitimate deduction, therefrom, that the greater portion 

 of the surfaces of natural gold are varnished over in this manner. 



Thus I have marked down those invisible, but none the less 

 formidable and real foes that we have to encounter, lurking 

 neither in the mercury, nor in the sulphides, but upon the gold 

 itself ; foes that have to be destroyed before amalgamation can 

 be thoroughly performed. 



In mitigation of any errors that may have crept into my paper 

 I may state that it was hurriedly prepared, at very short notice, 

 and that many of the experimental results detailed therein have 

 only just been obtained. 



4— THE PROPOSED CHEMICAL LABORATORY, AT 

 THE UNIVERSITY OF SYDNEY. 



By a. Liversidge, M.A., F.R.S., Professor of Chemistry and 

 Mineralogy in the University of Sydney. 



The need for proper accommodation for the Chemical Department 

 of this University is one of very long standing, and it has been 

 under the consideration of the Senate on many occasions for the 

 past fifteen yeai^s. As far back as 1873, it was almost as near 

 being an accomplished fact, as at the present time, and the 

 buildings would doubtless have been put up long ago, had it not 

 unfoi'tunately been found that certain extra and temporary 

 accommodation could be provided. This led to a series of make- 

 shifts from year to year, of a very inconvenient character ; 

 fortunately no more are possible, so that there is now a chance of 

 this department being suitably housed in a plain and unpretending 

 building, but one which, I trust, will be internally adapted to the 

 Avork to be carried on in it. 



