76 ON THE USK OP ALUMINIUM > 



" But that which renders aluminium pecu- 

 liarly adapted for artificial teeth, is its extreme 

 lightness, its specific gravity being only 2*60, 

 whilst silver is 10'47, and gold 19*26. Conse- 

 quently, silver is about four times heavier, and 

 gold more than seven times the weight of alumi- 

 nium." Three masses of solid metal, each about 

 the size and shape of a pigeon's egg, one of gold, 

 another of silver, and a third of aluminium, were 

 exhibited, and when taken in the hand they pro- 

 duced a very striking and decided idea of the great 

 difference between the relative weights of the 

 three metals. But for the information of those 

 who had not an opportunity of handling them, it 

 was stated that if a medal were made of alumi- 

 nium exactly the size and thickness of a crown 

 or five-shilling piece, it would be lighter than a 

 sovereign. 



The appearance of aluminium was also stated 

 to be greatly in its favour. In colour it is a 

 silvery lead, and where gold would be instantly 

 and distinctly seen in the mouth, the new metal 

 would escape detection under the same circum- 

 stances. Mr. Harrington considered a gold found- 

 ation to be far inferior to aluminium, except for 

 such artificial teeth as are intended to he exhibited 

 for ornamental display at shop doors, to attract the 

 eye of the casual passer by their shoivy appearance ; 

 but wjiere utility and comfort are required, he 

 considers a set made of aluminium to be worth 



