METALS. 



199 



water, and one of them, lithium, being lighter than any 

 known liquid. 



272. Color. The colors of almost all the metals are vari- 

 ous shades between the pure white of silver and the bluish 

 gray of lead. Bismuth has a reddish-white color. There 

 are only two metals that have very decided colors gold, 

 which is yellow ; and copper, which is red. 



273. Tenacity.- There is great variety in different metals 

 in their tenacity or power of holding together, iron being 

 the strongest and lead the weakest. This quality is tested 

 by using wires of the different metals of the same size and 

 appending weights to them, observing how much each wire 

 can possibly hold without breaking. In the following table 

 the experiments were made on wires one millimetre in di- 

 ameter: 



Metals. 



Breaking weight : 



wires one millimetre 



in diameter. 



Lead 3.1 Ibs 



Tin 6.9 



Cadmium 9.5 



Aluminium 18.0 



Zinc 23.5 



Gold 27.0 



Silver 29.0 



Copper 37.0 



Platinum 44.0 



(Brass 56.0 



Iron 56.5 



(Steel 96.0 



Relative 

 tenacity. 



1.00 



2.20 



3.06 



5.80 



7.58 



8.71 



9.35 



11.90 



14.20 



18.00) 



18.20 



30.00) 



274. Malleability. Malleability, derived from the Latin 

 word for hammer, is the capability of being beaten into 

 leaves. Laminability, from the Latin for leaf, lamina, is 

 sometimes used for the same quality, as exhibited when the 

 leaves are made by pressure rather than by blows, as when 

 iron and other metals are flattened by passing between 

 heavy rollers of steel. More properly it should be used as 



