With open-fire batteries for making the syrup, which was afterwards finished in the vacuum pan, very good sugar was produced, but at a cost that would be ruinous in to-day's markets.
An open fire acts by radiation; it warms the air in a room by first warming the walls, floor, ceiling and articles in the room, and these in turn warm the air.
Therefore in a room with an open fire the air is, as a rule, less heated than the walls.
Stoves were known, but most commonly heat was obtained from an open fire in the centre of the building.
When furs are wetted by rain they should be well shaken and allowed to dry in a current of air without exposure to sun or open fire.