198 Descriptions of various Modes of Heating bij Steam, 



roads, this is again covered with a bed of ashes, in which the pots 

 are placed as in the usual way. 



In lieu of the paving on the joists, boards, hurdles, or any other 

 material capable of supporting the weight above is equally appli- 

 cable. This mode has been in successful practice, nearly four years 

 in the Garden of Mr. Sturge of Lambridge near Bath, who con- 

 siders it greatly superior to the use of either dung, leaves, or tan, &c. ; 

 the temperature being at all times under the absolute control of the 

 attendant. 



This mode seems to have originated with Mr. Sturge, I having 

 heard of no other person using it previously to his trying the ex- 

 periment. 



For Bulbs, Cacti, fyc. 

 Fig 3 and 4, Plate 7, represent an elevation and plan exhibiting 

 the mode in which bottom-heat is applied to stoves for bulbs, Cacti, 

 &c. by the agency of steam. A paved water-tight bottom being built 

 on stones, earth or any suitable support, with a declivity towards 

 any convenient part of about one inch in ten feet to allow of 

 drainage; channels are formed about three inches deep and the 

 same width, crossing each other as shewn in Fig. 4, which also re- 

 presents two small steam pipes, each three quarters of an inch in 

 diameter closed at the farther end, and having perforations about 

 one tenth of an inch diameter opposite each other, and in the 

 middle of the channels. The result is that when steam is admitted 

 into the pipes it is discharged in opposite directions, through the 

 orifices, filling the whole space of the channels with hot vapour; 

 the channels being covered with brick or stone jointed without 

 mortar, as shewn in Fig. 3. ; the vapour which percolates between 

 the joints, is arrested by a bed of stones or broken bricks, similar 

 to those used in Fig. 1. and about fourteen inches in depth above 

 the paved bottom ; on this again is placed a bed of sand about one 

 foot deep, in which the pots are plunged to any suitable depth. 



