Page:On the economy of machinery and manufactures - Babbage - 1846.djvu/41

 degrees of force necessary to move these ponderous masses, will have varied according to the mechanical knowledge of the people employed in their transport; and that the extent of power required for this purpose is widely different under different circumstances, will appear from the following experiment, which is related by M. Rondelet, Sur L'Art de Bâtir. A block of squared stone was taken for the subject of experiment;

From this experiment it results, that the force necessary to move a stone along