452 INJURIOUS EFFECTS OF EICE CULTURE. 



Irrigation, as employed for certain special purposes in Europe 

 and America, is productive of very prejudicial climatic effects. 

 I refer particularly to the cultivation of rice in tLe Southern 

 States of the American Union and in Italy. The climate of the 

 Southern States is in general not necessarily unhealthy for the 

 wliite man, but he can scarcely sleep a single night in the vicin- 

 ity of the rice-grounds without being attacked by a dangerous 

 fever. The neighborhood of the rice-fields is possibly less pesti- 

 lential in Lombardy and Piedmont than in South Carolina and 

 Georgia, but stiU very insalubrious to both man and beast. " Not 

 only does the population decrease where rice is grown," says 

 Escourrou-MiUiago, " but even the flocks are attacked by typhus.* 

 In the rice-grounds the soil is divided into compartments rising 

 in gradual succession to the level of the irrigating canal, in order 

 that the water, after having flowed one field, may be drawn off 

 to another, and thus a single current serve for several compart- 

 ments, the lowest field, of course, still being higher than the 

 ditch which at last drains both it and the adjacent soil. This ar- 

 rangement gives a certain force of hydrostatic pressure to the 

 water with which the rice is irrigated, and the infiltration from 

 these fields is said to extend through neighboring grounds, some- 

 times to the distance of not less than a myriametre, or six Eng- 



posed of pebbles, gravel and sand, is dry in the Sik and through the town ; 

 but the infiltration is such that water is generally found by digging to a small 

 depth in the channel. Observing these facts in a visit to Petra in the summer, 

 I was curious to know whether the subterranean waters escaped again to day- 

 light, and I followed the ravine below the town for some distance. Not very 

 far from the upper entrance of the ravine, arborescent vegetation appeared 

 upon its bottom, and as soon as the ground was well shaded, a thread of water 

 burst out. This was joined by others a little lower down, and at the distance 

 of a mile from the town, a strong current was formed and ran down towards 

 Wadi el Araba, where it was again swallowed up by the thirsty sands. 



Similar facts are observed in all countries where the superficial current of 

 watercourses is diverted from their bed for irrigation, but this case is of 

 special interest because it shows the extent of absorption and infiltration even 

 in the torrid climate of Arabia. See Baird Smith, Italian Irrigation, vol. i., 

 pp. 172, 386 and 387. 



* According to Florence Nightingale, in India, fever rarely occurs in a vil- 

 lage surrounded by rice swamps, as long as the water is moving — living, as 

 the natives say. The fever time begins when the water falls and stagnates. — 

 Life and Death in India. 



