Spoken of the young Archimedes: . . . [he] was as much enchanted by the rudiments of algebra as he would have been if I had given him an engine worked by steam, with a methylated spirit lamp to heat the boiler; more enchanted, perhaps for the engine would have got broken, and, remaining always itself, would in any case have lost its charm, while the rudiments of algebra continued to grow and blossom in his mind with an unfailing luxuriance. Every day he made the discovery of something which seemed to him exquisitely beautiful; the new toy was inexhaustible in its potentialities.

Give me but a firm spot on which to stand, and I shall move the earth.

The diameter of the earth is greater than the diameter of the moon and the diameter of the sun is greater than the diameter of the earth.

The centre of gravity of any parallelogram lies on the straight line joining the middle points of opposite sides.

Archimedes to Eratosthenes greeting. ... certain things first became clear to me by a mechanical method, although they had to be demonstrated by geometry afterwards because their investigation by the said method did not furnish an actual demonstration. But it is of course easier, when we have previously acquired by the method, some knowledge of the questions, to supply the proof than it is to find it without any previous knowledge.

The centre of gravity of any cylinder is the point of bisection of the axis.

There are things which seem incredible to most men who have not studied Mathematics.