140 Notices of Communications to the Society, of which 



veyed with such strength to the lower part of the wall as to 

 injure the trees, as sometimes happens; 2nd, that the heat 

 supplied by the flue will be equally distributed over the en- 

 tire substance of the wall. It does not appear that any wall 

 has yet been executed upon this plan, the chief peculiarity 

 of which, is the interposing columns of air (which will receive 

 heat from the flue) between the flues and the external sur- 

 face of the wall ; this is proposed to be effected by forming 

 a hollow space from top to .bottom of the wall, between the 

 flue and the exterior surface of the wall : the air in this 

 being heated by the flue, and being contiguous to the whole 

 outer surface of the wall, its heat would probably be equally 

 distributed to every portion of the wall, and consequently 

 not in greater force to the bottom than to the top. 



Octorer 9th, 1819- Mr. Stoffels, of Mechlin, a Cor- 

 responding Member of the Society, in a letter to the Secre- 

 tary, read this day, mentions a discovery which he had acci- 

 dentally made of an advantageous mode of training Peach 

 trees. In the spring of 1818, he was obliged to strengthen a 

 wall, against which Peach trees were growing, by building 

 against it a buttress, three feet and a half wide, with an in- 

 clination of about fifty-one degrees. His gardener trained 

 some branches of a Peach tree upon this inclined plane, and 

 it was soon perceptible that vegetation was more vigorous 

 there, than where the tree was trained to the perpendicular 

 wall, for in a short time the quantity of young wood was so 

 great on the butlress, that room could not be found to train 

 " alliiMvlHlst on the upright wall there was hardly a sufficient 

 number of shoots to fill the v acant spaces ; and the fruit upon 



