Page:Philosophical Transactions - Volume 001.djvu/51

This page has been validated.


Papers of these Transactions; but the Press, employed upon this Treatise, having been retarded somewhat longer than was ghessed, the said promise could not be performed before this time: wherein it now concerns the inquiring World to take notice, that this subject, as it hath hitherto bin almost totally neglected, so it is now, by this Exceellent Author, in such a manner handled, and improved by near Two hundred choice Experiments and Observations, that certainly the Curious and Intelligent Reader will in the perusal thereof find cause to admire both the Fertility of a Subject, seemingly so barren, and the Author's Abilities of improving the same to so high a Degree.

But to take a short view short view of the particulars of this History, and thereby to give occasion to Philosophical men, to take this Subject more into their consideration, than hitherto hath been done; the ingenious Readers will here see,

1, That not only all sorts of Acid and Alcalizate Salts, and Spirits, even Spirit of Wine; but also Sugar, and Sugar of Lead mixed with Snow, are capable of freezing other Bodies, and upon what account they are so.

2, That among the Substances capable of being frozen, there are not only all gross sorts of Saline Bodies, but such also as are freed from their grosser parts, not excepting Spirit of Urine, the Lixivium of Pot-ashes, nor Oyl of Tartar, per deliquium, it self.

3, That many very spirituous liquors, freed from their aqueous parts, cannot be brought to freeze, neither naturally, nor artificially: And here is occasionally mentioned a way of keeping Moats unpassable in very cold Countries, recorded by Olaus Magnus.

4, What are the wayes proper to estimate the greater or lesser Coldness of Bodies; and by what means we can measure the intensness of Cold produced by Art, beyond that, which Nature needs to employ for the freezing of Water; as also, in what proportion water of a moderate degree of Coldness will