DENSITY OF SOLID MERCURY. 253 



VII. 



Th Denfity of Mercury in its folid State afcertaincd. By Mr. 

 John Biddle. 



To Mr. NICHOLSON. 

 SIR, Birmingham, March -!•, 1805. 



-£ A.T the Philofophical Society in Birmingham, of which I Experiments be- 

 am a member. I read a few weeks ago a lecture on mercury. ° re \ "5 r *$j 



.".-.. pnical Society in 



In the courfe of my experiments on this iubjeft, conducted Birmingham. 

 with a view of exhibiting this metal in a folid ftate, by ex- 

 posure to the frigorific mixture of muriate of Jime and fnow, 

 it appeared to me the fpecific gravity of this metal would be 

 moft accurately obtained in companion with other metals 

 under iimilar circumflances of folidity and temperature. I 

 therefore undertook, amongft a variety of others, the follow- 

 ing experiments, to afcertain its fpecific gravity in a folid 

 ftate, which I believe had never before been accompliflied : 

 They fucceeded to my fatisfaction, and to the gratification of 

 fome who were prefent : I am, therefore, inclined to be- 

 lieve, you will think them worth inferting in your Philofo- 

 phical Journal. 



I am very refpe&fully yours, 



JOHN BIDDLE. 



HAVING purified mercury, by diitilling from an earthen Mercury wa? pu- 

 retort into a glafs receiver 50 per cent, of the quantity put in, r ! fied ."^ dlftllu ~ 

 to avoid the alloy of any other metal, and afterwards having 

 heated it to 300° of Fahrenheit, to drive off any water that 

 might adhere, fuch as was ufed in other experiments, and 

 expofed to the aftion of muriate of lime and fnow, — I pro- 

 ceeded as follows : 



One thoufand grains of this mercury were introduced to the and expofed to 

 freezing-mixture, together with three ounces of alcohol, in ^° n £ 6 ] un er 

 a round-bottomed glafs ; and having placed in the mercury 

 a fine bent wire, the weight of which was previoufly known 

 when immerfed in the fame alcohol, to a certain point, in the 

 temperature of 47 degrees above zero of Fahrenheit : this wire, 

 during the congelation of the mercury, was fixed in if, fo 



that 



