A DISCOURSE

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of the Description of the Western Isles of Scotland tells us, that, uponhis own experience, a rod of Oak , of four, five, six, or eight inchesabout, being twisted like a wyth, boiled in wort, well dried, andkept in a little bundle of barley-straw, and then steeped again in wort,causes ft to ferment, and procures yeast. The rod should be cut beforemid-day, and is frequently used in this manlier to furnish yeast, and,being preserved, will serve, and produce the same effect many yearstogether j and, as the historian affirms, that he was showed a pieceof thick wyth which had been kept for making ale with for above twentyyears' 1 . In the mean time, the leaves of Oaks abundantly congestedon snow, preserve it as well, for wine, as a deep pit, or the most artificialrefrigeratory. Nor must we pafs by the sweet meldews, so much morecopiously found on this tree than any other, whence the industriousbees gather such abundance of honey, as that, instead of carryingit to their hives, they glut themselves to death : But, from this ill report,hastily taken up by Euricius Cordus , our learned Mr. Ray has vindicatedthis temperate and abstemious useful creature. Varro affirms they madesalt of Oak ashes, with which they sometimes seasoned meat, but morefrequently made use of it to sprinkle among, and fertilize their seed-corn ; which minds me of a certain Oak, found buried somewherein Transylvania , near the salt-pits, that was entirely converted intoan hard salt when they came to examine it by cutting. This experiment,if true, may pofsibly encourage some other attempts for the multiplyingof salt. Nor lefs strange is that which some report of a certain water,somewhere in Hungary , which transmutes the leaves of this tree intobrafs, and iron into copper - ’. Of the galls is made trial of spaw-water,

h It is a practice in some parts of this country to dry yeast upon cap-paper, placedin a -wicker basket, in order that the ale may filtre through. A small portion of this dried.cake, beaten up with warm water and a little pot-ash, makes an extemporaneous fermentfor bread.

* Brafs is a factitious metal, and never discovered in a natural state; so that whatjjVlr. Evelyn here says must be regarded as fabulous. With respect to what he mentions. of iron being converted into copper, there .is the appearance of truth in the experiment.In Ireland there is-a spring, in which, if plates of iron are laid, they will be converted,in a few weeks, into copper: But in this case there is a fallacy, and no real transmutation.The particles of iron are corroded by the acid in the water, and the particles of the copper,minutely suspended in the menstruum, are deposited in their place. In this mannerconsiderable quantities of copper are collected.