Tho’ this water does not deposit any sediment, yet it is remarkable for the speedy and strong incrustation of all bodies, which are put into it. Little plaister figures are sold here, on purpose to verify the experiment; which, tho’ perfectly white when put into the spring, are, in eight-and-forty hours, entirely covered with a yellow incrustation. The same effect is observed on the pipes and channels, thro’ which the water is conveyed. If care were not taken to clean them four or five times a year, they would be intirely choaked up; and in some parts, where it has not been necessary to clean them so often, I have seen them covered with an incrustation two inches thick. In surrounding and covering these wooden pipes, they do not change the nature of the wood; but it is observable, that they add great hardness and solidity to it: so that it is affirmed a piece of deal will last a hundred years in this water. The head spring is cleared out once in 30 or 40 years, with a very great expence: at which time they are obliged to break off all the stony incrustation, which had been made by the water since the last cleaning; and if neglected would (as it has sometimes actually done) choak the passages, and oblige the spring to find vent in some other place. The incrustations formed by these waters are of different kinds: that, which is made in the troughs and pipes, thro’ which the water is conveyed after it comes above ground, is of a light sandy nature, of a loose contexture, and a bright yellow. It is used by the inhabitants as a gentle corrosive for eating off proud flesh. There is another of a darker colour, and a much harder nature, which is found at the very mouth of the spring, where it bursts out of the rock. There are other sorts taken out of the subterraneous cavities of the spring at the time it was cleaned. In what manner they are formed, is not so easy to determine; unless there were an opportunity of observing in what manner and direction they lie within the spring. They seem to be an alabastrine spar, and are beautifully marked with strait veins of different colours, which may be supposed to have received their tinge from the different colour of the spring-water at the time when this sediment, or rather scum, was formed upon it. They find pieces of this kind most beautifully variegated; and some of them large enough, by fineering to make tables: these polish very well, and are not much inferior to jasper in appearance. It is a part of the manufacture of the place, to work this sort of stone into snuff-boxes, cane-heads, and sleeve-buttons.