The mean variation of the magnetic needle was 21° 55' 

 And the mean of the dipping needle was 72° 26'. 



XXI l. Of the Manner in ivhich the Russians treat Persons needed by the Fumes 

 of Burning Charcoal, and other Effluvia of the same Nature. By Mattheiv 

 Guthrie, M. D. p. 3'15. 



People of condition in this country have double windows to their houses in 

 winter ; but the commoner sort have only single ones ; which is the reason that 

 during a severe frost, there is an incrustation formed on the insides of the glass 

 windows. This seems to be composed of condensed breath, perspiration, &c. 

 as a number of people live and sleep in the same small room, especially in great 

 cities. This excrementitious crust is further impregnated with the phlogiston of 

 candles, and of the oven with which the chamber is heated. When a thaw 

 succeeds a hard frost of long duration, and this plate of ice is converted into 

 water, there is a principle set loose, which produces all the terrible effects on the 

 human body which the principle emitted from charcoal is so well known to do in 

 this country, where people every day sufl^er from it. However, the Russians 

 constantly lay the blame on the oven, when they are affected by the thawing of 

 the crust, as the effects are perfectly similar, and they cannot bring themselves 

 to believe, that the dissolving of so small a portion of ice can be attended with 

 any bad consequence, when they daily melt larger masses without danger : yet 

 the oven does not at all account for the complaints brought on at this period ; 

 for, on examination, they generally find every thing right there, and still the 

 ugar, or hurtful vapour, remaining in the room. As the effects of both are 

 similar, and also the mode of recovery, I shall only give an account of the ope- 

 ration of the principle emitted by burning charcoal, and of the method of 



