THE FARMER AT HOME. 



473 



when they are too broad at the extremity, the orifice is often so large 

 that the cow cannot retain her milk after the bag begins to be full 

 and heavy. The udder should be nearly of the same size, before and 

 behind, or, if there be any difference, it should be broader and fuller 

 before than behind. 



YORKSHIRE COW. 



ZEBRA. An animal of the horse kind, and a native of the 

 southern parts of Africa. This creature is rather less than a mule, 

 is exceedingly wild, and amazingly swift. Its shape is elegant ; its 

 hair fine and smooth ; its head, its neck, and its whole body is striped 

 in such a manner as to resemble a garment made of the finest ribands ; 

 and it is in all respects one of the most beautiful of animals. 



ZINC. A semi-metal of a whitish color, nearly resembling that 

 of lead, though it does not so speedily tarnish. It is of great utility 

 in the arts. Combined with gold, in equal portions, it forms a hard 

 white compound, that admits a fine polish, and may be advantage- 

 ously manufactured into specula, for optical instruments. Zinc and 

 tin, melted together, produce a kind of pewter ; and as the former 

 spreads more uniformly, while it is much harder, and less fusible than 

 tin, it has been proposed as a substitute for the latter, in tinning cop- 

 per vessels. Zinc and copper readily unite in the fire, forming a 

 metal distinguished by the general name of yellow copper ; but which 



