6 MAC Leod, The Place of Science in History. 



Archimedes was a mathematician. To the geo- 

 metrical science of his time he added many very important 

 propositions, and the geometrical method followed by 

 Euclid was improved by him, and became in his hands 

 almost equivalent to integration, an achievement of 

 modern science. One of his greatest discoveries was the 

 measurement of the circle, a discovery which opened the 

 way for many more calculations. 



Moreover, Archimedes did splendid work in physics. 

 His treatise on floating bodies contains the general 

 principles of hydrostatics ; among other things the dis- 

 cussion of the positions of rest and stability of a solid 

 body floating in a fluid. Several of the propositions 

 contained in that treatise are among the classic instances 

 expounded in modern text-books of physics. 1 



Archimedes showed himself brilliantly capable of 

 turning his scientific knowledge to practical account. 

 One of his most ingenious inventions is the so-called 

 screw of Archimedes, or water screw, which was used 

 through the ages, and is still used to raise water. It was 

 probably devised in Egypt for purposes of irrigation. 



On one occasion, Hiero, king of Syracuse, wishing 

 to ascertain whether a crown, which had been made for 

 him, and which purported to be of pure gold, did not con- 

 tain a proportion of silver, referred the question to Archi- 

 medes. Archimedes was puzzled, but after long reflection 

 he devised his test. It occurred to him that if the crown 

 were an alloy of gold and silver, then, since silver is 

 lighter than gold, the volume of the crown would be 

 greater than that of an equal weight of pure gold. The 

 volume of the crown was determined by placing it in 

 a vessel filled with water and measuring the overflow, 



1 lie discovered, among other things, the principle in hydrostatics 

 which bears his name. 



