Complete Extant Works of Hero of Alexandria, Vol. 2 (1900) - Page 12

		Page
18 (18).	Each revolution of a screw shifts a tooth of the engaging wheel by its own width	141
19 (19).	Effect of steep and shallow screws on the tylos a mechanical component or adjustment nut and vice versa	141
20 (20).	Obstacles to the effect of the simple powers	145
21 (21).	Effect of a system of wheels on axles	149
22 (22).	Ratio of force and time in this machine	153
23 (23).	Effect of a system of pulley blocks	155
24 (24).	Ratio of force and time involved therein	157
25 (25).	Effect of a system of levers	159
26 (26).	Ratio of force and time in this case	161
27 (27).	With wedge and screw, the same force acts more powerfully as they become smaller	163
28 (28).	Ratio of force and time for wedge and screw	163
29 (29).	Combining simple powers, other than the wedge, to move a load	163
30 (30).	The sharp wedge requires less force. The blunt wedge	167
31 (31).	Construction of a screw for a given tylos mechanical component	169
32 (32).	Reinforcement of forces due to friction	171
33 (33).	Natural principles for explaining phenomena	171
34 (34).	Answers to 17 mechanical-physical questions	175
35 (35).	Finding the center of gravity of a triangle	189
36 (36).	Center of gravity of a quadrilateral	191
37 (37).	Center of gravity of a pentagon	193
38 (38).	Distribution of the load of a triangle on the supports under its vertices	193
39 (39).	Distribution of a load placed at an arbitrary point of a

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