Mathematicall Magick

Ch. 14. Concerning the infinite strength of wheels, pulleys, and screws; that it is possible, by the multiplication of these, to pull up any oak by the roots with a hair, lift it up with a straw, or blow it up with one’s breath, or to perform the greatest labor with the least power.

Ch. 15. Concerning the proportion of slowness and swiftness in mechanical motions.

Ch. 16. That it is possible to contrive such an artificial motion as shall be of a slowness proportionable to the swiftness of the heavens.

Ch. 17. Of swiftness, how it may be increased to any kind of proportion. Concerning the great force of Archimedes his engines. Of the ballista.

Ch. 18. Concerning the catapultae, or engines for arrows.

Ch. 19. A comparison betwixt these ancient