vi Proceedings. [Xoven/bcr ph, igo2. 



Ordinary Meeting, November 4th, 1902. 



Charles Bailey, M.Sc, F.L.S., President, in the Chair. 



The thanks of the members were voted to the donors of the 

 books upon the table. The following books were included 

 amongst the recent donations to the Society's library: — '^T/ie 

 Ficiio?i of the Ice Age or G/acial Period" hy F. D. Longe ',8vo., 

 Lowestoft, 1902), presented by the author ; ''The P]iarmacological 

 Action and Therapeutic Uses of the AUtrites and Allied Coinpoiuids,^' 

 by the late Professor D. J. Leech, edited l)y Professor R. B. 

 Wild (8vo., Manchester, 1902), presented by Mrs. Leech; 

 "Catalogue of the Library of the Zoological Society of London,^' 

 5th edition (8vo., London, 1902), presented by the Society; and 

 '■'■International Engineering Congress ( Glasgow), igoi. Report of 

 the proceedings and abstracts of the papers read'' (Svo., Glasgow, 

 1902), presented by the Executive Committee of the Congress. 



Mr. Thomas Thorp, F.R A.S., exhibited specimens of 

 aluminium he had soldered by the method of M. Margot 

 mentioned in Prof. Threlfall's book "Laboratory Arts." 



The aluminium is first cleaned by rubbing with warm potash 

 and fine sand, washing off and drying. It is then heated over 

 a clean flame, so as to melt the solder (an alloy of 92 per cent, 

 of tin and S per cent, of zinc). The pieces of the metal required 

 to be soldered are both treated in the above manner and 

 " sweated " together. Mr. Thorp has found that no previous 

 cleaning is required if the solder be run on to the metal and 

 well rubbed in, whilst hot, with a stick of asbestos. When the 

 surface appears bright, an amalgam has been formed, and the 

 solder immediately adiieres. In order to solder (say) brass 

 to aluminium, the brass must be tinned in the usual way and 

 flooded with pure tin. On the two metals being heated to a 

 little above the melting points of the solders, independently, 

 and placed together, a firm joint results. 



Sir William H. Bailev exhibited the working model 

 of the switchback centrifugal railway invented and made by 



