Rensselaer Gazette, Volume 2, Number 42, Rensselaer, Jasper County, 9 February 1859 — Curious Scientific Facts. [ARTICLE]

Curious Scientific Facts.

<- , ; A-slight blow is sufficient to smash a whole , pane .of glass, while a bullet from a gun will ‘ only make a small round hole in it; because I in the latter case, the particles of glass that receives the blow are torn away from the , remainder with such rapidity that the mo- ' tion imparted to them has no time to spread further. A door standing open, which would readily yield on its hinges to a gentle push, is not moved by a cannon ball passing through I it. The ball, in passing through, overcomes ■ the whole force of cohesion among the atoms ! of wood, but its force "acts for so short a ! time,-owing to its rapid passage, that it is ■ not sufficient to affect the inertia of the door ito an extent to produce motion. The cohe- ! ' sion of the part of the wood cut out by the j ball would have borne a very great weight' j laid quietly upon it; but suppose the ball to ■ fly at the? rate of twelve hundred feet in a ; second, and the door to be one inch thick, , the cohesion being' allowed to act for only 1 the.minute part of a second, its influence is not. perceived.' It is an effect of this same '■ principle that the iron head of a hammer may be driven down on its wooden "handle, by ■ striking the opposite end of the' handle against tiny hard substance with force and I speed- In this very simple operation, the motion propagates so suddenly through the ! wood of the handle, that it is over before It i can reach the iron head, which, therefore, by its own weight, sinks lower on the hani die at every blow, which drives the handle up.