A HISTORY OF SCIENCE 



same weight was similarly immersed ; lastly the crown 

 itself was immersed, and of course for the story must 

 not lack its dramatic sequel was found bulkier than 

 its weight of pure gold. Thus the genius that could 

 balk warriors and armies could also foil the wiles of 

 the silversmith. 



Whatever the truth of this picturesque narrative, 

 the fact remains that some such experiments as these 

 must have paved the way for perhaps the greatest of 

 all the studies of Archimedes those that relate to the 

 buoyancy of water. Leaving the field of fable, we 

 must now examine these with some precision. Fort- 

 unately, the writings of Archimedes himself are still 

 extant, in which the results of his remarkable experi- 

 ments are related, so we may present the results in the 

 words of the discoverer. 



Here they are : " First: The surface of every coherent 

 liquid in a state of rest is spherical, and the centre 

 of the sphere coincides with the centre of the earth. 

 Second: A solid body which, bulk for bulk, is of the 

 same weight as a liquid, if immersed in the liquid will 

 sink so that the surface of the body is even with the 

 surface of the liquid, but will not sink deeper. Third : 

 Any solid body which is lighter, bulk for bulk, than a 

 liquid, if placed in the liquid will sink so deep as to 

 displace the mass of liquid equal in weight to another 

 body. Fourth: If a body which is lighter than a 

 liquid is forcibly immersed in the liquid, it will be 

 pressed upward with a force corresponding to the 

 weight of a like volume of water, less the weight of the 

 body itself. Fifth : Solid bodies which, bulk for bulk, 

 are heavier than a liquid, when immersed in the liquid 



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