396 THE COMMON OX. 



lands, and the number of their cattle. It is in these 

 that all real wealth consists: every other kind,, even 

 silver and gold, are only arbitrary representa- 

 tives, which have no value but that which is con- 

 ferred upon them by the productions of the 

 earth*." 



Oxen attain maturity at the age of about eighteen 

 months, or two years. From this age, till they are 

 nine years old, they are in their greatest vigour; 

 and the duration of their lives seldom exceeds 

 fourteen or fifteen years. The period of gestation 

 in the females is fprty one weeks; and they usually 

 produce only a single Calf at a birth. It is a remark- 

 able fact, that when a Cow happens to produce two 

 Calves, of different sexes, at the same time, the 

 male is always perfect, but the female is incapable 

 of continuing the species, and is known to farmers 

 by the name of Free Martin. 



With respect to the diseases to which these ani- 

 mals are liable, the principal seem to be fevers of 

 different kinds, murrain or pest, inflammation in 

 the lungs or liver, and loss of cud. Cattle are 

 poisoned by eating yew, hemlock, or aconite; and 

 they often die in consequence of eating gross suc- 

 culent clover, which fills and distends them with 

 wind to an amazing degree. 



* Buffou par Sonnini, xxiii. p. 13. 



When 



