248 On the Management of Hothouse Flues. 



are usually enjoying themselves before a comfortable fire, at 

 some of the above periods, and in their warm beds, at others, 

 the poor gardener is obliged to encounter the pitiless pelting 

 of rain, snow, or hail, the cold pulses of the frosty air, or the 

 piercing shafts of the northerly blasts, in regularly pacing to 

 and from his furnace (in many cases no doubt at a considera- 

 ble distance from his lodgings ) without the allowance of a 

 single intermission during the tedious winter. 



But surely these matters may be managed otherwise. The 

 common baking oven, after fuel has been burning therein 

 about two hours, when the fire is removed and the door clos- 

 ed, retains a high degree of heat for twenty or thirty hours ; * 

 Although, in the mean time, it has been somewhat cooled 

 by the evaporation from the bread, in baking, as well as by 

 the door standing open whilst the same is being withdrawn, 

 and although (as in my case) the door be of iron, which, from 

 its known conducting quality, rapidly transmits the heat into 

 the atmosphere in contact with it. Why then do we not adopt 

 the ovenian principle (to borrow Mr. Jeremy Bentham's 

 license) in our stoves and hothouses, and by closing up the 

 furnaces and flues, after they have been properly heated, at 

 an early hour in the evening, and re-opening them, and 

 rekindling the fires, at an hour not inconvenient in the morn- 

 ing, at once spare the gardener's nightly rest, and the master's 



* In attempting to measure the heat of my oven on the morning after it had 

 been heated in the middle of the preceding day, by placing therein a brewing ther- 

 mometer, in the tube of which the mercury had the power of rising no higher 

 than 210°, the bulb in a short time burst. The heat therefore, I think, must have 

 exceeded that point. Having been so unfortunate, I did not make any further 

 attempt. 



