?5B Contribution toivards the assayhig of Coins. 



of vital air. (^Plde my Philosophy of Medicine, case xxxiv,' 

 vol. i. p. 497.) This observation iS \\'orthv of regard to' 

 8iicH as are obliged to have recourse to tlii:^ remedy, as 3 

 solace during night, labouring under irremediable disease. 



8. The sudden death produced by drinking of lemonade, 

 when hot by dancing, shows that the oxygen is hastily ab- 

 sorbed ; and no such effect being produced, if a little spirit 

 be added, is a further proof how these principles (viz. hy- 

 drogen and oxvgcn) balance each other. 



9. The practice of taking persons out who ate swoon- 

 ing, or in a state of intoxication, into the open air for 

 thcir''fecover\-, depends upon the supply of oxygen to the 

 system, then deficient. 



Sir, I have been more anxious to record such cases, asJ 

 the accidents by opium are much more frequent than from 

 any other means. In tlic one case above recorded, the lady 

 went to. different shops and got a small supply from each, 

 and then drank off the aggregate. Other poisons are not 

 easily procured. I shall conclude in the memorable words 

 of sir George BrathvvaiteBoiighton* : — ''If it can he of anij 

 use in a science ivhich has for its object , tlie case and liappi- 

 iiess of mankind, I shall always look lack uith pleasure to 

 these accidents ivhich have afforded me an opportunitij (f 

 giving you this deta'iL" 



I am, sir, your obedient servant, 



Robert John THORNXOisr; 



[My next commimication, will be the case of a physician 

 cured by the inhalation oi vital air, every other means hav- 

 ing previously failed.] 



XLIV. A Contribution towards tlie assaying of Coins. By 

 Professor Klaproth. 



In this essay I shall first give an account of the process t 

 employed : I shall then exhibit the component parts of the' 

 coins I examined, and conclude with some oljservations de- 

 duced from my experiments. 



I found by some previous experiments that on the earlier 

 Greek coins, besides copper, the principal component part, 

 I had to direct mv attention to tin and lead as essential ad- 

 ditions, and to iron and silver as accidental mixtures; and 

 in the Roman coins to a considerable quantity of zinc. Tn 



* In a letter wntYcK to and published by Dr. Beddoies. 



