ON THE HISTORY OF MECHANICS. 181 



although we cannot attempt to enter into a complete history of mechanics, 

 it may still be satisfactory to take a short retrospect of a few of the most 

 remarkable eras in mechanical philosophy, and in those parts of mathe- 

 matics on which it immediately depends. 



It is universally allowed that the Greeks derived the elements of mathe- 

 matical, mechanical, and astronomical learning from Egypt and from the 

 East.* Diogenes Laertius, who appears to be very desirous of claiming for 

 his countrymen the merit of originality, does not deny that Thales and 

 Pythagoras acquired much of their knowledge in their travels. Thales of 

 Miletus is the first that can be supposed to have introduced these studies 

 into Greece. Moeris, who was probably a king of Egypt, and Theuth or 

 Thoth, a native of the same country, are mentioned as having laid the foun- 

 dations of geometry ; but the science could scarcely have extended, in 

 those ages, further than was barely necessary for the measurement of land : 

 since Thales, or even a later philosopher, is said to have first discovered 

 that two lines drawn from the extremities of the diameter of a circle, and 

 meeting in any other part of its circumference form with each other a right 

 angle. Thales was one of the seven whom antiquity distinguished by the 

 appellation of wise men ; he flourished about 600 years before the Christian 

 era, and he was the father of the Ionian school, the members of which, in 

 subsequent times, devoted themselves more particularly to the study of 

 moral than of natural philosophy. 



The Italian school, on the contrary, which was founded by Pythagoras, 

 appears to have been more inclined to the study of nature and of its laws ; 

 although none of the departments of human knowledge were excluded from 

 the pursuits of either of these principal divisions of the Grecian sages, until 

 Socrates introduced into the Ionian school a taste for metaphysical specu- 

 lations, which excluded almost all disposition to reason coolly and clearly 

 on natural causes and effects. To Pythagoras philosophy is indebted for 

 the name which it bears ; his predecessors had been in the habit of calling 

 themselves wise, he chose to be denominated a lover of wisdom only. He 

 had studied under Pherecydes, and Pherecydes under Pittacus : but with 

 respect to mathematical and mechanical researches, it does not appear that 

 either of his teachers had made any improvements. On his return from 

 his travels in Egypt and the East, in the time of the last Tarquin, about 

 500 years before Christ, he found his native country Samos under the do- 

 minion of the tyrant Polycrates, and went as a voluntary exile to seek a 

 tranquil retreat in a corner of Italy. At Croto, says Ovid, he studied and 

 taught the laws of nature. 



" From human view what erst had lain concealed 

 His piercing mind to open light revealed ; 

 To patient toil his ardent soul constrained, 

 Of Nature's richest stores possession gained : 

 And thence, with glowing heart and liberal hand, 

 He dealt her treasures o'er the listening land. 

 The wondering crowd the laws of nature hears, 



And each great truth in silent awe reveres." 



* See Kelland's Lectures on Demonstrative Mathematics, Edinb. 1843. Lect. I. 



