374' ON SWEETENING WATER USED AT SEA. 



As the stowing the water in tanks was considered as an experi- 

 ment, the water in the casks was used in preference 5 that in the 

 tanks being reserved for occasions of necessity, excepting that a 

 small quantity of it was used occasionally for the purpose of ascer- 

 taining ils purity, or when the water in the casks was deemed, 

 when compared with that in tank.*, too bad for use. 



The water in thirteen of the tanks, on-board one ship, and in all 

 the tanks on. board the other, was always as sweet as when first 

 taken from the source ; but in the oilier three of the tanks, on-board 

 one ship, the water was found to be more or less tainted as in the 

 casks. This difference, however, is easily accounted for, by sup- 

 posing that the water of these taiiks was contaminated before it 

 was put into them; for in fact the whole of the water was brought 

 on-board in cask;;, for the purpose of filling the tanks, and no 

 particular care was taken, to taste the water at the time of taking 

 it on board 



After the water kept in this manner had remained on-board a 

 length of time which was deemed sufficient for experiment, it was 

 used out, and the tanks were replenished as occasion required : 

 but in some of the tanks, on-board one ship at least, the original 

 water had remained three years and a half. About twenty-five 

 gallons of the water, which had remained this length of time in the 

 ship, were sent to the Society, in two vessels made of the same sort 

 of tinned copper with which the tanks were lined. 



A certificate from Captain William Bolton, commander of the 

 said vessel, dated Sheerness, 2Sth of June, 1800, accompanied this 

 letter, stating that the water delivered to the Society was taken 

 from a tank holding about seven hundred gallons, and which his 

 predecessor, Captain Portlock, had informed him had been poured 

 into the tank in December 171)6, except about thirty gallons added 

 in 1798, and had remained good during the whole time. 



In a letter, dated January 7, General Bentham also states, that 

 the water which had been preserved sweet oil-board his Majesty's 

 sloops Arrow and Dart, was taken from the well at the king's brew, 

 house, at Weevil, from whence ships of war, lying at or near 

 Portsmouth, are usually supplied with water for their sea-store, 

 as well as for pressent use." 



EDITOR. 



