Greenhouses and Hothouses. 249 



of a heating apparatus should not only increase in proportion 

 to the increased size of the house, but for every increase in 

 the area of ihe house, the proportion of the area of radiation 

 should be doubled. In general, this rule is exactly reversed, 

 — the power decreasing as the house is enlarged! What 

 proof can be afforded of the adaptability of an apparatus by 

 warming a pit that might be as efficiently warmed by a com- 

 mon tea-kettle, or what satisfactory evidence can such facts 

 afford of the superior adaptability of Polmaise for these pur- 

 poses ! 



Those who are thoroughly acquainted with the principles 

 upon which hothouses ought to be heated do not appear to 

 be very numerous, if we are to judge from the specimens 

 that are commonly erected ; and there are fewer still who 

 appear willing to undertake laborious and patient experiments, 

 which are necessary to bring more practical facts to light on 

 this subject. In fact, this subject, important though it be, 

 seems fairly bound up by absolute indifference. Nobody ap- 

 pears willing to harrass themselves by so unaccustomed 

 investigations. People are willing to take any one's advice 

 rather than trouble themselves much about inquiries, and, 

 therefore, in attempting to show the inferiority of Polmaise, 

 as a system of heating, it is necessary to resort to arguments 

 which appeal not only to practical demonstration, but will 

 also stand the test of scientific examination. If half were 

 true that has been published in favor of Polmaise, it would 

 long ere now have been firmly established upon the basis of 

 its own merits, and instead of struggling for existence as a 

 theoretical novelty, it would have quickly silenced all oppo- 

 sition by its consummate excellence. 



The first care of the builders of a new system is to de- 

 molish the fabrics that are standing ; and the chief aim of 

 the advocate of a new method is to decry the other methods 

 that have been in use before it. Thus, we have a number 

 of heating systems that are praised by some and condemned 

 by others, without having any very definite testimony of 

 the merits of either. The opinions of one person are con- 

 demned by another, and thus we find truth, sophistry, and 



VOL. XVI. NO. VI. 32 



