Adams Papers

[Winthrop’s Lectures on Experimental Philosophy.] April 1st. 1754.


[Winthrop’s Lectures on Experimental Philosophy.] April 1st. 1754.1

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 ex­plained, 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 {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 {11} that of the ram, as much as the ram exceeds the Cannon in weight, that is as 36:40000.

1This is the true beginning of JA’s notes on Professor John Winthrop’s lectures; he had first started them two pages earlier in the MS and then canceled that beginning for reasons explained in the note there (p. 55, above); see also note on entry of 19 March 1754, above.

All the notes on Winthrop, which continue through 11 April, are in JA’s variant or experimental hand of 1754–early 1756, discussed in the Introduction.

2The “Course” or series of lectures on Experimental Philosophy was required by the terms of the Hollis professorship to be given at least once a year. Designated “private lectures,” they were intended only for the sophisters (Endowment Funds of Harvard University, Cambridge, 1948, p. 55–56; Morison, Three Centuries of Harvard description begins Samuel Eliot Morison, Three Centuries of Harvard, 1636–1936, Cambridge, 1936. description ends , p. 80). The terminal dates of a course of lectures such as this did not coincide with term times but rather with the period between March and the end of June when senior sophisters were required to be in Cambridge; see note on entry of 29 June 1753.

The notes taken by JA on the lectures indicate that the course as begun in 1754 was to be essentially the same as the thirty-three lectures prepared by Professor Winthrop for delivery one to five times a week (ordinarily three), from 10 March to 16 June 1746, a lecture-by-lecture summary of which in Winthrop’s hand, with additions for 1747, is preserved in MH-Ar: “The Summary of a Course Of Experimental Philosophical Lectures, by Mr. J. Winthrop.” A facsimile of Winthrop’s outline of the first lecture is reproduced as an illustration in the present volume.

3Editorially supplied for a careless omission in MS. Winthrop’s “Summary” does not mention the towers.

4Thus in MS.

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