28 BALCH— THE LAW OF ORESME, [April 23, 



gold and silver, as between gold and silver minted vinder the same stamp; 

 as also that the same ratio applies to gold coins and gold bars as to silver 

 coins and silver bars, provided that they have the same proportion of alloy 

 and that they represent the same weight." 



As Oresme and Copernicus explained to their royal masters that 

 by either debasing or raising the coins of the realm disaster and 

 confusion would follow, so also, at the beginning of Queen Eliza- 

 beth's reign, one of her merchants, Sir Thomas Gresham, pointed 

 out to his royal mistress this inflexible unwritten law of money. 



Of a Norfolk family, the son of Sir Richard Gresham, who was 

 Lord Mayor of London, Sir Thomas Gresham was born in that city 

 probably in 1519, and died there on November 21, 1579. He was 

 educated at Cambridge University, was a Protestant, and all his life 

 took an active part in commercial affairs, often representing in the 

 Low Countries the commercial interests of England. In 1566 and 

 1567 he built the Royal Exchange in London. He founded also 

 Gresham College, and provided that the science of astronomy should 

 be taught there. 



In a letter to Queen Elizabeth, which is headed " information of 

 Sir Thomas Gresham, Mercer, touching the fall of the exchange, 

 MDLVIII," and which begins, " To the Queues most excellent 

 maiestye," Gresham says : 



" Ytt may pleasse your majesty to understande, thatt the firste occasion 

 off the fall of the exhainge did growe by the Kinges majesty, your latte 

 ffather, in abasinge his quoyne ffrome vi ounces fine to iii ounces fine. 

 Whereuppon the exchainge fell ffrome xxvis. viiid to xiiis. ivd. which was 

 the occasion thatt all your ffine goold was convayd ought of this your realme." 



The works on money of these three men, who, independently of 

 one another, expounded to their respective sovereigns the evils 

 resulting to the State from any attempt to debase the coinage, did 

 not become generally known to their contemporaries. However, 

 their discoveries through the influence of their royal rulers gradually 

 made some impress upon mankind, and by the end of the seventeenth 

 century it had become common knowledge among the intellectuals of 

 that day. In a pamphlet published in London in 1696, the Law of 

 Oresme, Copernicus and Gresham, though doubtless the writer did 

 not know directly of their works, is thus stated : 



