378 GEOGRAPHICAL BOTANY. 



the conditions of the climate and soil in a more tangible 

 and definite style than was the case in the first volume, 

 which treated of the East (Reisen in Europa, Asien, und 

 Africa, Bd. 2. Stuttgard, 1843-45. In 1844, appeared 

 the first part of this volume, including Egypt and Nubia, 

 and the first number of the second part, containing 

 Eastern Soudan). The climate of Lower Egypt, as far as 

 Cairo, is that of the Mediterranean a wet winter (ii, 

 p. 263) and a serene summer. In Cairo we find the 

 rainless zone of the north of Africa. At Cairo, according 

 to the quinquennial average of Clot Bey, there are twelve 

 rainy days in the year, with 0'034m. of rain. The ab- 

 sence of rain, both in Upper Egypt (Cairo to Nubia) and 

 in the Sahara, depends upon constant north winds ; hence 

 Egypt is climatically a part of the Sahara. 



The swollen state of the Nile, produced by the tropical 

 rainy season, lasts from June to the end of September 

 (i, p. 229). The months of October and November form 

 the period at which the Cerealia are sown in those tracts 

 of ground which are artificially flooded by canals ; the 

 harvests occur in February and March. Here, accord- 

 ing to the kind of grain, a second crop may be sown in 

 April, and reaped immediately before the irrigation. In 

 other fields, the crop cannot be sown until December or 

 January, and only once reaped, in May. 



Sketch of the most important Branches of Cultivation, arranged according 

 to the usual period at which the Crops are Sown and Reaped. 



SOWN. HARVEST. 



January. Beans (Cerealia). Sugar-cane. 



February. Rice, maize. Barley, melons. 



March. Cotton. Cerealia, maize. 



April. (Cerealia.) 



May. Tigs, dates, grapes (Cerealia). 



June. Beans (Cerealia). 



July. Cotton. 



September. Oranges, olives, rice. 



October. Cerealia. Rice. 



November. Cerealia. Maize. 



December. (Cerealia.) 



