OUT THE HISTORY OF MECHANICS.

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fc he extremities of the diameter of a circle, and meeting in any other part ofits circumference form with each other a right angle. Thales was one of theseven whom antiquity distinguished by the appellation of wise men; lienourished about GOO years before the Christian era, and he was the father ofthe Ionian school, the members of which, in subsequent times, devoted them-selves more particularly to the study of moral than of natural philosophy.

The Italian school, on the contrary, which was founded by Pythagoras ,a Ppears to have been more inclined to the study of nature and of its laws; al-though none of the departments of human knowledge were excluded fromtile pursuits of either of these principal divisions of the Grecian sages, untilSocrates introduced, into the Ionian school, a taste for metaphysical speculations,'vhich excluded almost all disposition to reason coolly and clearly on naturalcauses and effects. To Pythagoras , philosophy is indebted for the name

t^hich it bears; bis predecessors had been in the habit of calling themselves

ivise; he chose to be denominated a lover of wisdom only. He had studiedUnder Pherecydes , and Pherecydes under Pittacus : but with respect to mathe-matical and mechanical researches, it does not appear that either of his teach-ers had made any improvements. On his return from his travels in Egypt andHie East, in the time of the last Tarquin, about 500 years before Christ, hefound his native country Samos under the dominion of the tyrant Polycrates ,an d went as a voluntary exile to seek a tranquil retreat in a corner of Italy .

Croto, says Ovid , he studied and taught the laws of nature.

“ From human view what erst had lain concealedHis 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.”

Ho

wever erroneous the opinion may be, that Pythagoras was acquaintedthe laws of gravitation, it is certain that he made considerable improve-

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