APPENDIX. 



On Heating, Ventilating or Aerating, and Covering. 



Since the publication of the first edition of this work 

 in 1844, the views expressed in the second chapter, 

 with reference to structures best adapted for Cucum- 

 ber culture in the winter season, have met with much 

 corroborative support. Respecting the questions of 

 heating, ventilation, and covering, a few more words 

 may be added. 



I have before recommended hot water tanks for sup- 

 plying bottom heat, with attached pipes for the circu- 

 lation of hot water to warm the atmosphere. I can 

 see no reason for recommending any other arrangement 

 now ; for the experience of successive years goes to 

 show that hot water, applied on sound principles, is, 

 above all other means of heating, effective in its opera- 

 tion ; and as to the question of expense, raised as an 

 objection to it by some, it is sufficient to say, that, 

 although one hot water apparatus may be fitted up in 

 an expensive manner, another may be rendered per- 

 fectly successful in its operation, at the same time that 

 it is extremely simple in its arrangements, and corres- 

 pondingly inexpensive in its cost. 



A seeming error in the engraving, at p, 18, has 

 been pointed out to me. In the description of the 

 sketch it is stated that, " a series of pipes attached to 

 the same boiler [which heats the tank] would supply 

 the requisite heat to the atmosphere." The sketch 

 itself shows these pipes to be considerably above the 

 level of the water in the tank, and where they could 

 not, consistently with the other arrangements, be thus 



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