528 On the Quantity of Carbon in the Blood. 



be built and paved to be moft healthy, to wit, the calcareous ; 

 and that a wife policy fhould introduce marble and lime Hone 

 into general ufe. 



it. The ufe of pit-coal for fuel has an additional recom- 

 mendation. During combuftion it afford? much ammoniac: 

 and this volatile alkali is capable of neutralising abundance of 

 feptic acid. Commonly, where the burning of coal is ge- 

 neral, peftilential diftempers are more rare than they ufe to 

 be. But my paper fails me before I have finifhed my enu- 

 meration : I mull therefore conclude, and leave the reft for a 

 future communication, though not without affuring you that 

 I remain yours, with much regard and refpect, 



To A. Tilloch, Efq. SAM . L. M ITCHILL. 



Vni. Extracl of a Letter from ProfeJ/br Abildgaard, 

 Secretary to the Royal Society at Copenhagen, to C. Hu- 

 ZARD, Member of the French National I/filute, on the 

 Quantity of Carbon in the Blood*. 



I 



SHALL give you the refult of fome experiments which 

 I made and repeated to difcover the quantity of carbon that 

 exifts in the blood, and which gave me lefs of that fubftance 

 in the arterial than in the venous blood. 



1 ft, A hundred parts of the venous blood of a horfe, when 

 dried in a moderate heat, gave 36 parts of a fubftance fo dry 

 that it could be pulverifed. 



2d, A hundred parts of arterial blood of the fame horfe 

 gave 25 parts of dry fubftance, 



3d, To alkalife, in the manner of Kirwan, an ounce of 

 nitre by detonation (the ounce being 480 grains), required 

 192 grains of venous blood, and only 160 of arterial. 



4th, An ounce ©f venous blood, after being dried and de- 

 compofed in a clofe veffel, yielded 115.; grains of charcoal. 



5th, The fame quantity of arterial blood gave only 8,; [, 

 grains of charcoal. 



6th, To decompofe 480 grains of nitre, required ] 48 grains 



* From the Anna! a de Cbimie, No. 106. 



of 



