"6. Charcoal fires in pots are used chiefly in the shops of handicraftsmen. They warm a room (that is kept close, and has no chimney to carry off the warmed air,) very speedily and uniformly; but, there being no draft to change the air, the sulphurous fumes from the coals (be they ever so well kindled before they are brought in, there will be some,) mix with it, render it disagreeable, hurtful to some constitutions, and some times, when the door is long kept shut, produce fatal consequences."