Complete Extant Works of Hero of Alexandria, Vol. 2 (1900) - Page 14

		Page
I,	1. The winch	257
	11. The Delian problem (doubling the cube)	267
II,	1. The wheel and axle	273
	2. The lever	277
	3. The pulley and the pulley block	277
	4. The wedge	281
	5. The screw	283
	6. Combination of screw and wheel and axle	287
	7. Concluding remark on the 5 simple machines	291
	18. The endless screw	291
	35. The center of gravity of a triangle	293
III,	1. The 'tortoise' (rolling sledge)	295
	2. The crane with one mast	297

(Latin).

		Page
	Introduction	303
I.	Hearing and sight. Harmony of the spheres. Classification of optics	318
II.	1st and 2nd Proposition: Visual rays form straight lines and move with infinite speed	321
III.	3rd Proposition: When visual rays are reflected	323
IV.	4th Proposition: Fundamental law of reflection: Equality of the angle of incidence and reflection. Reflection occurs along the shortest path. Proof of this with the plane mirror	325
V.	5th Proposition: Proof of this with the convex mirror	329
VI.	6th Proposition: No image when the point of incidence is covered	331
VII.	7th Proposition: Reflected rays neither converge nor are they parallel. Proven for plane mirrors	331
VIII.	8th Proposition. The same proven for convex mirrors	333

CONTENTS