274 TFatei' Supph/. 



and filled have been known for periods of twenty or tlilrty years 

 never to become dry; the summer of 18(J4 was a notable excep- 

 tion, in which, during the months of April, May, June, July, 

 and August, a less quantity of rain fell in the neighbourhood in 

 question than for the thirty years preceding, and dew was noted 

 deficient. A calculation, based on carefully obtained facts, 

 shows that in 40 days, ending Julv 14th, 1864, a pond lost (by 

 measurement of its surface and depth) 13,500 gallons of Avater ; 

 adding the known rainfall, 0"9, on the slopes and surface of the 

 pond — 1800 gallons — we have a total of 15,300. Calculating the 

 consumption of a flock of sheep, 500, at ^ gallon per head 

 per day; the Cjuantity used by cottagers at GOO gallons; the 

 evaporation, as tested by experiments, at 9000 ; the sum stands 

 thus ; — 



"Water lost bv iioiul l-'i-oOO ) ,- oaa 



Jiaiuiall 1,<SU0 j ' 



Consumed by Slieep ] 0,000 ) 



Cottaiics COO [ I9,r>00 



Evaporation 11,000 ) 



Xot accoiuited for 4,300 



' It is believed that -?,- a gallon per dav does not represent suffi- 

 cient water for each sheep's consumption. It was found that a 

 flock of ewes on dry food consumed 10 pints, or 1|- gallon per 

 day, in the winter of 1864-5. Taking only f of a gallon, the 

 consumption would be e([ual to the whole loss. The concurrent 

 testlmonv of manv shepherds bears out this supposition. 



Apart from all such calculations, shepherds say that they see 

 vapours gathering over the ponds ; and a person of undoubted 

 intelligence assured the writer that he has seen the vapours 

 drawn to the ponds, as to a centre, when unmoved by Avind. It 

 is readily acknowledged that this subject requires further inves- 

 tigation ; but, as a fact, the value and endurance of the supply to 

 these ponds can hardly be denied. In many parts of the chalk 

 range — especiallv where partially covered with Avoodlands — these 

 ponds are not known, and here they might be profitably intro- 

 duced ; and it is believed that they would be found valuable on 

 all high and exposed districts where summer supplies of water 

 are needed. 



The collection of surface-water from drains in a clay subsoil, 

 even where the contour of the ground favours such an arrange- 

 ment, must be precarious. These drains do not run except after 

 heavy rainfalls ; ponds which retain their water during a long 

 period might be filled by these means, but, in the absence of 

 supply from land or other springs, the quantities so stored would 

 be likelv to j'ail, 



