320 APPLICATION OF PRINCIPLES. 



In some parts of Persia, Armenia, and Mesopo- 

 tamia, the summer heats are excessive, while the win- 

 ters are rendered cold by the proximity of moun- 

 tains. Bagdad is described as having a cold winter, 

 because of the proximity of the mountains of Koor- 

 distan; yet its heats are intense: in August, 1819, 

 the thermometer stood at 120° in the coldest parts 

 of the house, and at 108° at midnight in the open 

 air. This was preceded by heavy rains, which raised 

 the Euphrates 7^ feet above the ordinary level : the 

 whole country was like a vapour bath, and multi- 

 tudes of persons dropped down dead : twenty-two in 

 three days in a single caravan. In the northern pro- 

 vinces of Mexico the winters are of German rigour, 

 while the summers are those of Naples and Sicily 

 the Tierra fria of that country has, however, a very 

 different climate, the mean heat of the summer being 

 76', and the winters so mild that the thermometer 

 only occasionally falls below 32°. 



At the Cape of Good Hope there are districts 

 in which the period of wet is long and very severe ; 

 and many of the favourite flowers of our gardens are 

 produced by those districts. The Karroos are plains 

 of great extent, destitute of running water, with a soil 

 of clay and sand, coloured like yellow ochre by the 

 presence of iron, and lying on the solid rock. Dur- 

 ing the dry season the rays of the sun reduce the 

 soil nearly to the hardness of brick ; Fig Marigolds, 

 Stapelias, and other fleshy plants, alone remain green ; 

 nevertheless, the bulbs and tribes of Iridaceous and 

 other plants are able to survive beneath the sun- 



