ALEXANDRIAN OR HELLENISTIC PERIOD 



to batter the wall: trusting in the great multitude of 

 his engines of battery, and to all such other necessary 

 provision as he had for wars, as also in his own reputa- 

 tion. But Archimedes made light account of all his 

 devices, as indeed they were nothing comparable to 

 the engines himself had invented. This inventive art 

 to frame instruments and engines (which are called 

 mechanical, or organical, so highly commended and 

 esteemed of all sorts of people) was first set forth by 

 Architas, and by Eudoxus: partly to beautify a little 

 the science of geometry by this fineness, and partly 

 to prove and confirm by material examples and sensi- 

 ble instruments, certain geometrical conclusions, where- 

 of a man cannot find out the conceivable demonstra- 

 tions by enforced reasons and proofs. As that con- 

 clusion which instructeth one to search out two lines 

 mean proportional, which cannot be proved by reason 

 demonstrative, and yet notwithstanding is a principle 

 and an accepted ground for many things which are con- 

 tained in the art of portraiture. Both of them have 

 fashioned it to the workmanship of certain instru- 

 ments, called mesolabes or mesographs, which serve 

 to find these mean lines proportional, by drawing cer- 

 tain curve lines, and overthwart and oblique sections. 

 But after that Plato was offended with them, and 

 maintained against them, that they did utterly cor- 

 rupt and disgrace, the worthiness and excellence of 

 geometry, making it to descend from things not com- 

 prehensible and without body, unto things sensible 

 and material, and to bring it to a palpable substance, 

 where the vile and base handiwork of man is to be em- 

 ployed : since that time, I say, handicraft, or the art of 



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