80 FLORA INDICA. 



siderably lowered the temperature of that province, (the arid 

 plains of the Panjab, however, remaining excessively heated,) 

 it becomes S.S.E., and in September still more easterly. 



In the eastern (Malayan) peninsnla it is probable that the 

 direction of this monsoon is nearly from south to north ; but 

 more detailed information is required to enable us to under- 

 stand the precise course of the aerial current in all parts of 

 that Peninsula. At the commencement of the monsoon the 

 wide and open valley of the Irawacli seems to act as a local 

 source of attraction, to which the wind blows from both 

 oceans. At a later season, the elevated temperature of the 

 plain of the Ganges and the Tibetan valley of the Brahma- 

 putra overpowers that influence, and the main atmospheric 

 current flows over the mountains south of Assam and as- 

 cends the valleys of both these rivers in a north- westerly di- 

 rection. 



II. The north-east or winter monsoon. As a consequence 

 of what we have stated, after the autumnal equinox, the great 

 mass of the Himalaya becomes intensely cold, and the whole 

 of the continent comparatively cool, while the southern hemi- 

 sphere gets powerfully heated. The north-east monsoon, 

 which results from this distribution of temperature, is the 

 effect of a distant attraction, and therefore blows with great 

 regularity. It is everywhere a land wind, except in the Ma- 

 layan Peninsula and on the coast of the Carnatic. In Ma- 

 laya it blows over a great extent of sea, and is therefore very 

 rainy ; but in the Carnatic the width of sea is not great, so 

 that the rain-fall, though well marked, is less, and terminates 

 long before the end of the monsoon, probably from the wind 

 acquiring a more directly southerly direction, after the sun 

 has reached the southern tropic. 



The current which flows towards the southern hemisphere 

 as the north-east monsoon, is replaced by an upper one which 

 flows northward. It is from this northerly current, which 

 arrives moisture-laden from the southern ocean, that are de- 

 rived the winter snows of the Himalaya and of the mountains 



