1ET. VII. AND DISCOVERIES. IQH

ground ; and would fall still farther, if there wasa hole in the earth, and nothing hindered itspassage. And the fame thing happens to allother bodies, with which we are acquainted:there is no material substance, either great orsmall, but what will fall towards the earth themoment it is disengaged, and free from all out-ward impediments.

In like manner it may be observed, that whena stone or any other body is placed upon a table,it presses the table with the fame force, by whichit would, if left to itself, fall to the ground.And when a body is suspended at the end of astring, the force that pushes it downwardsstretches the string, and if it is not sufficientlystrong, will break it. From which circum-stances it plainly appears, that all bodies presswith a certain force against those obstacles whichsupport and hinder them from falling; and thatthe degree of force, in either case, is preciselythe same with that, which in a free space wouldbring them to the ground.

The cause of this propensity in all bodies tofall to the earth, be it what it may, is called gra-vitation or attraction ; and when a substance issaid to be heavy, nothing more is meant thanthe tendency it has to fall to the ground; or theforce by which it presses upon any other bodythat supports it. The weight and gravity of abody may, therefore, be taken for the same

thing;