By Mr. Martin Miller Call. 471 

 is otherwise lost by escaping in the chimney. In fixing the 

 iron tube in the flue, it should be observed to allow for the 

 expansion and contraction of the iron, so that it may be 

 able to move backwards and forwards in a socket, as shewn 

 in the front flue at X. 



In the front of the house the Vines are laid in a horizontal 

 position, and covered with an inclined light, Q, until the 

 season arrives when we wish to force them ; the light is then 

 taken entirely away ; and the Vines are left in this manner 

 until we perceive the buds have made a general push ; by 

 this method we find the eyes break more regularly. 



POSTSCRIPT. 

 February 5, 1821. In the preceding account I have 

 stated that I find heating the boiler once a week produced 

 the desired effect. In making that statement, J omitted 

 to observe that part of the heat of the house was occasioned 

 by the tan wherein the pots were plunged. On the removal 

 of the tan, and the substitution of earth in its place, I 

 have found it requisite, in order to create a proper tem- 

 perature for the Pine plants, to heat the steam boiler once 

 in every four days. The object in substituting earth for tan 

 was to try how the Pines planted in the earth, without pots, 

 would grow, in comparison with the usual plan. I expected 

 to succeed with the experiment, and the result has answered 

 my expectations ; the plants thus treated are much superior 

 in all points. 



vol. IV. 



