47 
gl. Iron is of specific gravity 7700. Its other 
properties are well known. The number repre- 
senting it is 103. 
gg. Tin is of specific gravity 7^91 ; it is a very 
fusible metal, and burns when ignited in the air : 
the number representing the proportion in which 
it combines is 110. 
23. Cadmium is a newly-discovered metal, very 
similar to tin in its sensible properties, of specific 
gravity about 9000, and is very fusible and volatile. 
24>. Zinc is one of the most combustible of the 
common metals. Its specific gravity is about 7^10. 
It is a brittle metal under common circumstances ; 
but when heated may be hammered or rolled into 
thin leaves, and after this operation is malleable. 
The number representing it is 66. 
25. Lead is of specific gravity 11352; it fuses 
at a temperature rather higher than tin. The 
number representing it is 398. 
^6. Bismuth is a brittle metal of specific gravity 
9 822. It is nearly as fusible as tin ; when cooled 
slowly it crystallizes in cubes. The number re- 
presenting it is 135. 
27 . Antimony is a metal capable of being vola- 
tilized by a strong red heat. Its specific gravity 
is 6800. It burns, when ignited, with a faint white 
light. The number representing it is I70. 
28 . Arsenic is of a blueish white colour, of 
specific gravity 8310. It may be procured by 
heating the powder of common white arsenic of 
the shops strongly in a Florence flask with oil. The 
metal rises in vapour, and condenses in the neck 
of the flask. The number representing it is 90. 
