Browsing: Early Diary of John Adams, Volume 1

Mr. Winthrop began a series of Experimental Phylosophy2, and in the 1st place he explained to us the meaning, nature, and excellence of natural phylosophy, which is, (he says) the knowledge of those laws by which all the Bodys, in the universe are restrained, it being evident that not only those great masses of matter the heavenly Bodys, but all the minutest combinations of matter in each of them are regulated by the same general laws. For instance it is plain that all the planets observe exactly the same uniform rules in their revolutions round the sun, that every particle of matter observes on the surface of the earth.—As to the usefulness of natural phylosophy, to be convinced of that, it is necessary only to reflect on the state of all the Civilized nations of Europe, compared to many nations, in affrica, of as quick natural parts as Europeans, who live in a manner very little superiour to the Brutes.—The first Cause, and indeed the alpha and omega of natural phaenomena, is motion, their being an utter impossibility that any effect should be produced in a natural way without motion, and <this motion or rather Bodys in motion are subject to the following laws, 1st two bodys of different velocitys or swiftnesses, but aequal masses> which motion is subject to Certain laws which he ex• {p. 61} plained, and I have forgot. But thus much I remember, that motion, produced by gravity, was universally in right lines, from the body acted upon by gravity, to the Center of gravity, as the Center of the earth, for instance, or the like. He explained also, powers, weights, the line of direction of powers and weights, the Center of gravity, Center of {Folio: 10} magnitude, and Center of motion, with the several methods of finding them, some of which I’ve forgot, and the rest he showed us examples of which cant easyly be exhibited. But by reason of some of these laws (he tells us) there are two famous towers in Italy, the one at Bolognia, and the other at [Pisa] 3, each near an hundred feet high which are not in a perpendicular position, but inclined to the horizon to a Certain degree, so as not to have the line of direction fall without the Base, because if the line of direction fell not within the Base, the buildings would inevitably fall. After this and many other things and Terms relating to motion, velocity &c. explained he dismiss’d us for the first time.—He touch’d also upon the advantages of gunpowder in war, above those of the Battering ram. For says he, the Battering ram was a hugh,4 and unweildy peice of timber or rather combination of timbers, with an iron head much in the shape of a rams head, whence it drew its name, commonly weighing near forty thousand Pounds, and consequently required a 1000 men to manage it, a man being scarce able to handle more than 40 lb. with velocity enough to do execution. Now one of our cannon, by the almost irresistable force of rarifyed vapour will discharge a 36 pounder so as to make as large a Breach in a wall, as the Battering ram, and requires but <about 6> 5 or 6 men to order and direct it. Therefore 6 men can do as much execution now with a Cannon as 1000 could with a Battering ram, and the momenta are equal the velocity of the Cannon exceeding {Folio: 11} that of the ram, as much as the ram exceeds the Cannon in weight, that is as 36:40000.