132 EFFECTS OF FORESTS ON MOISTURE. 



medicinally in cases of dysentery. There is a neat cottage at 

 Palmer's, in which a man and his wife reside, and take care of a 

 garden producing chilies and pumpkins, 



" In December 1831 the main pipes were finished, being led from 

 Bate's tank at Dampier's, 5 miles distant from the garrison, and 1000 

 feet above its level, and the same depth below the Mountain tank. 



"In January 1832 an octagon iron tank, capable of containing 20 

 tons, was placed under the drip in Breakneck Valley, and in the same 

 year a tnnnel was cut through the mountain about 930 feet long, for 

 pipes to convey the water, which was pumped by horse power, and 

 forced up 140 feet into an iron tank above the level of the reservoir 

 on the other side of the mountain. The tunnel is sufficiently wide 

 and high to admit of people walking through with ease, and is a 

 wonderful proof of the perseverance and skill of the marines, who, 

 under Captain Payne, executed it in the short period between 19th 

 May and 3rd October of the same year. The principal and only 

 certain supply of water is obtained through this. 



"InFebruary 1847 there was a great scarcity of water, and distilling 

 was first commenced with Clark's apparatus, but as salt water was 

 obtained from a well sunk in the square, affected by the ebb and flow 

 of tide, the supply was limited and uncertain. 



" I found the drips in 1861 much in the same state as they appear 

 to have been in 1832, and shall describe the present water resources 

 of the island, the steps that have been taken to improve them, and 

 the plans I would suggest to ensure an adequate supply. 



" The drips and wells in Breakneck Valley are the only sources that 

 never entirely fail, although the yield is considerably less after a long 

 drought ; the drips are caused by the rain and wet fogs, arrested by 

 the steep sides of the ravine, and percolating through the cinder to 

 strata of rock, which crop out and form ledges. Under these, lengths 

 of zinc and iron sheeting were placed, conducting the water in driblets 

 to a small cemented trough over the octagon tank, which occasionally 

 overflowed after heavy rains, and at all times the labour of forcing a 

 column of 140 feet of water was very distressing to animals, and 

 absorbed much labour. 



" In the latter end of 1863, a wind engine of 1| horse power, by 

 Bury and Pollard, was erected near the octagon tank ; the pipes were 

 connected throughout their whole extent, as they were found to be 

 too much on a dead level to carry ofi" the water forced up, and we had 

 the satisfaction of finding that it worked admirably, and was capable 

 of doing much more when required. 



