150 scientific notes. 



The use of aluminium is not making much progress ; and now, 

 I believe, it is only made in Paris. 



It is used in instruments where extreme lightness is required, 

 as in tubes for telescopes. But the bronze made years ago by 

 Colonel Strange, though as strong as steel, proved so uncertain in 

 castings that it had to be given up, and the instrument which was 

 intended to be all bronze was finished in brass. Messrs. Mathey & 

 Johnson, of Hatton Garden, London, have been trying to alloy it 

 with other metals, and find that a small percentage of nickel adds 

 greatly to its hardness, but does not make it take solder ; and 

 to melt up filings seems rather an expensive luxury, for, out of 

 twenty ounces put into the pot, only five of solid metal were 

 obtained. The retail price now is 52s. a pound. 



[During the reading of the paper Mr. Russell exhibited interest- 

 ing diagrams and beautiful photographs.] 



