TEMPERATURE. 397 



Continental horses, as regards latitude. For instance, the 

 latitude of the Steppes of the Don is lower than that of 

 England, but the winter temperature of the former country 

 is at least 40° F. lower than that of the latter. 



With regard to altitude, we have the well-known fact 

 that Mountain Welsh ponies are from one to three hands 

 smaller than Welsh ponies which are brought up on land 

 that is from 1,000 to 2,000 nearer the level of the sea. 

 Although the lowland Welsh ponies have been much 

 " improved " by the introduction of new blood, they were 

 formerly of the same breed as their mountain compatriots, 

 but a nearly similar difference of height existed between 

 the two. In the Shetland Islands, where the warming 

 influence of the Gulf Stream is not so great as farther 

 south, the combined effects of latitude and altitude in 

 creating cold, have made an equine dwarf in the form of 

 the ten hand Sheltie. As an instance of reduction of 

 height produced solely by high altitude, we have the 

 twelve hand Battak pony (Fig. 439), which is bred in 

 Sumatra, on or close to the Equator, but on high moun- 

 tains. The fact that he is largely crossed with Arab 

 blood does not free him from the effect of his cold climate. 

 This dwarfing influence of a high altitude is well shown 

 by the small size of Himalayan ponies, such as those of 

 Bhutan, Nepal and Spiti. An average fall of temperature 

 is about 1° F. to every 300 ft. of altitude. 



Cold, in diminishing height, produces this effect, chiefly 

 in reducing the length of the limbs, but it does not 

 decrease the animal's vigour to any appreciable extent. 

 Thus, the afore-mentioned Finnish, Mountain Welsh, Shet- 

 land, Battak, and Himalayan ponies are short legged, 

 hardy and strong for their size. Excess of climatic heat, 

 on the contrary, reduces the size of the body to a much 

 greater extent than the length of the limbs, and con- 

 sequently diminishes the animal's comparative strength, 

 as we may see in Figs. 417, 440 and 441. In fact, many 

 Eastern ponies are longer on the leg and lighter in the 



