in Philosophy, a small drop or vehicle of any fluid filled with air; and formed either on its surface by an addition of more of the fluid, as in raining, &c.; or in its substance, by an intestine motion of its component particles. Bubbles are dilatable or compressible, i.e. they take up more or less room as the included air is more or less heated, or more or less pref-

fed from without; and are round, because the included air acts equally from within all around.

in commerce, a cant term given to a kind of project for raising money on imaginary grounds, much practised in France and England in the years 1719, 1720, and 1721.

The pretence of those schemes was the raising a capital for retrieving, setting on foot, or carrying on, some promising and useful branch of trade, manufacture, machinery, or the like. To this end proposals were made out, showing the advantages to be derived from the undertaking, and inviting persons to be engaged in it. The sum necessary to manage the affair, together with the profits expected from it, were divided into shares or subscriptions, to be purchased by any disposed to adventure therein.

Bubbles, by which the public have been tricked, are of two kinds, viz. 1. Those which we may properly enough term trading bubbles; and, 2. Stock or fund bubbles. The former have been of various kinds; and the latter at different times, as in 1719 and 1720.