Gradual drijing up of the River Arica. 349 



sinking into the soil, so that, at a depth of two or three feet, 

 one comes upon water, or, at all events, moisture, while tlie 

 surface remains burned to a cake. A little canalization of 

 the river-bed, and damming up the water, so as to have a 

 permanent reservoir, would not merely secure a better supply 

 of water, but would most beneficially influence the salubrity 

 of the neighbourhood. The river dries up entirely every 

 year in the months of July and August, during which accord- 

 ingly occur the largest number of cases of sickness, and it 

 seems the more necessary that measures of some sort should 

 be at once taken to control the water, as otherwise there is 

 reason to fear that unless artificial dykes and dams be con- 

 structed, the bed of the river will gradually be sanded up, 

 when the whole district will be worse off for water than ever; 

 since with each successive year's floods, as they dash down 

 from the mountains, a perceptible falling off in quantity has 

 been remarked, so that whereas ten years ago the bed of the 

 river was full for four or five months together, at present it is 

 rarely full so long as two months in all. 



On 22nd May, we entered the little harbour of Port d'Islay, 

 the access to which is very difficult. The settlement itself 

 stands on a steep rock, 150 feet high, descending almost ])ev- 

 pendicularly into the sea on all sides, so that the only land- 

 ing-place is a mole, which communicates with the village 

 above by an iron ladder. The well-known traveller. Count 

 Castelnau, who in the course of a scientific expedition through 

 South America visited this port in 1848, prophesied a splen- 



