. The book of the garden. Gardening. HOTHOUSE FURNACES. 257 which escapes by the chimney. The restoration of the current of air causes the smoke to cease and the flame to reappear. In these essentials the smoke-consum- ing furnaces differ widely from those in common use, because, in the latter, no air can possibly reach the back part of the furnace at the bridge, but is admitted at the front of the fire close by the door, and, in consequence, passing rapidly over the fire, enters the throat of the furnace at the bridge in an improperly heated form, and not only carries along with it a large qu
. The book of the garden. Gardening. HOTHOUSE FURNACES. 257 which escapes by the chimney. The restoration of the current of air causes the smoke to cease and the flame to reappear. In these essentials the smoke-consum- ing furnaces differ widely from those in common use, because, in the latter, no air can possibly reach the back part of the furnace at the bridge, but is admitted at the front of the fire close by the door, and, in consequence, passing rapidly over the fire, enters the throat of the furnace at the bridge in an improperly heated form, and not only carries along with it a large quantity of smoke, but also a great portion of cold air, which, instead of heating the flues, tends rather to reduce their tempera- ture. In regard to that part of the furnace called the bridge, Mr Ainger, in "Gar- deners' Chronicle," makes the following remarks: — "In ordinary boiler-setting, what is called the bridge, which is in- tended to direct the rising flame and gases into close contact with the boiler, but which, at the same time, shuts out a large space from its radiation, is, I be- lieve, a totally injurious contrivance. By diminishing the primary radiation of the boiler, we, of necessity, give a larger por- tion of heat to the gases which it is suffi- ciently difficult to reclaim during their rapid passage through the thereby over- heated flues, and which escape with an unnecessary large share of heat into the ; Our own opinion of the exclusion or admission of atmospheric air is, that a very limited quantity is all that is neces- sary, both for the support of combustion and also for the consumption of smoke; but that this air, whatever its amount may be, should be directed to the warm- est part of the furnace;—and the warmer it is before it is so applied, the better. Air- tight furnaces should be first constructed; and, if provided with proper registers in their frames and ash-pit doors, the neces- sary quantity of air can be most readi
Size: 1681px × 1486px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1850, booksubjectgardening, bookyear18
