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111.

[[image:  drawing of recumbent T, upright A B, horizontal to the right C D E F, labeled I where the horizontal attaches to the upright, with a ball or weight [[presumably G]] suspended from F.]]

Galileus hath written a Tract of ye resistance of solids, where he gives ye same definition of ye absolute resistance and explains after his manner ye forte wch a weight ought to have suspended at ye end of a solid fastened in a wall as if ye wall is A B and ye solid C D E F and that ye weight G [[missing from diagram]] is suspended in F by ye cord F G [[ditto]], he says that ye length F D is like ye arm of a lever and that ye thickness C D is as a contralever, so that if we would generate a part in C and that its absolute resistance be 20 pound ye weight G need only be 2 pound, if ye length F D was 5 times greater than D C:  But in considering another part as I equally distant from C and D, there [[strikethrough]] be [[/strikethrough]] need [[strikethrough]] not [[/strikethrough]] be but one pound in G because ye lever F D would be then 20 times greater than ye counterlevel D I;  and because that he supposeth that ye rupture is made in ye same time in all ye parts of C D [[strikethrough]] ye ?? [[/strikethrough]] whereof same between I and C, and ye others between D and I, he pretends that we must consider ye augmentation of ye force of the weight according to ye proposition of F D to ye mean distance D I, which is against many experiments wch I have made with solids of wood and glass, where I have found that we must take ye proportion E D to a line less than B I, as ye fourth of D C or 1/3 &c, and not of F D to ye half of D C.  To find this proportion and refute that of Galileus I made ye following considerations.

  I suppose first that ye wood, iron and other solid bodys have their fibers and their [[?ramous]] parts interlaced one with another, and that they cannot be seperated but by a certain force and that they make all together ye firmness and resistance of ye body to be broken when we draw them perpendicularly from ye top to ye bottom acording to their length:

  That these parts may be extended more or less by different weights, and that there is an extension they cannot suffer without being broken so that if it is necessary that a solid of wood be extended 2 lines to be broken, and that a weight of 500 pounds can make that extension a weight of 115 pounds will extend it but about 1/2 a lines that of 250 pounds but about a line &c and that so each extension will make an equilibrium with a certain weight.

Transcription Notes:
mandc: amended the image description, changed J's to I's. Image: http://echo.mpiwg-berlin.mpg.de/ECHOdocuView?url=/permanent/library/QERNH1MN/pageimg&viewMode=images&mode=imagepath&pn=283&ww=0.1262&wh=0.1825&wx=0.5374&wy=0.7076