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the vegetable, all the common metallic bodies, gold, sil-ver, copper, iron, tin, lead, zinc, bismuth, reguluS of an-*timony, cobalt, &c. yet in solution of platina it producesno precipitation or turbidness ; so that when this alcali ismixed with a solution of gold containing platina, the goldalone is precipitated, and all the platina remains dissolved.The manner of obtaining this alcali from the acid withwhich it is united in sea salt, as it would in this place toomuch interrupt the history, is referred to the appendix.

The mineral alcali is in many places, particularly in theeastern countries, found native, either in a pretty pure state,or blended chiefly with earthy substances, from which it iseasily separated by solution in water., I have been fa-voured by Dr. Heberden with a quantity of this native saltsent to him from Teneriss, and find that it answers thepresent intention as effectually as the alcali extracted fromlea salt. The solution of platina effervesced with it, butin whatever proportions the solution of the alcali and ofthe platina were mixed together, I could not observe theleast precipitation or cloudiness.

A salt of the same nature, though generally perhapsmingled with some foreign saline matters, is obtained fromthe asses of certain plants, called Kali, which growingchiefly in salt marsses or on the sea ssore, the marine saltis supposed to be imbibed by them, and to be decom-pounded, or to have its acid separated, partly by the powerof vegetation in the plant itself, and partly by the burning.The best sort of these asses is said to be prepared at Ali-cant in Spain,, from an annual procumbent kali with ssortleaves like those of houseleek.. The asses, which are oneof the common kinds of potass in France* and there calledsoude or soda, are brought to us, under the name of Spanifoajhes or bariglia , in hard spongy masses, partly whitiss or0rey, and partly blackish. From these masses the saline

part.