Mr. C. proceeds to shew that this malady is occasioned by a calcareous matter called in Swiss _Tuf_; and adds, "This stone resembles very much the incrustations at Mallock in Derbyshire, which dissolve so completely in the water as not to lessen its transparency; and I think that the particles of this substance so dissolved, resting in the glands of the throat, occasion the Goitres, and during the course of my travels in different parts of Europe, I have never failed to observe, that where this _Tuf_, or calcareous deposit is common, _Goitres_ are equally so. I have found an abundance of tuf, and also of goitrous persons in Derbyshire, the Valois, the Valteline, at Lucerne, Berne, Fribourg, in parts of Piedmont, in the valleys of Savoy, at Milan, and at Dresden. I also observed that at Berne and Fribourg, the public fountains are supplied from sources where there is a vast quantity of this calcareous deposit. General Pfiffer has informed me, that there is but one spring at Lucerne, which is free from tuf, and that those who reside in its vicinity, are much less subject to the goitres than the rest of the inhabitants. A surgeon also, whom I met at the baths of Louesch, informed me that he had _frequently_ extracted from different goitres _small pieces of tuf_, which is also found in the stomachs of cows, and the dogs of this country are also subject to this malady. This gentleman added, that, to complete the cure of young persons attacked by this complaint, he either removed them from waters impregnated with tuf, or recommended them to drink only of water that had been purified. The children of goitrous parents are often born with these swellings; but there are also instances of children born with goitres, whose parents are free from them."