SECTION V. 



VARIOUS METHODS OF HEATING DESCRIBED IN 

 DETAIL. 



THE heating of hot-houses, by any of the ordinary methods 

 of warming these structures, has hitherto been attended with 

 extravagant expense. The difficulty of obtaining, at a reason- 

 able price, the means of keeping up the desired temperature, 

 during long and severe winters, the expense of the apparatus, 

 the annual cost of repairs, the continual outlay for fuel, 

 together with the incidental expenses and trouble of working 

 them, has, in many instances, proved a barrier to their erection, 

 and has induced many to abandon the attempt, who had well 

 nigh carried it into execution. Many lovers of exotic gardening 

 have thus been diverted from the enjoyment of this pleasant and 

 healthful pursuit; and hence it is of the utmost importance, 

 especially to amateurs and others having small establishments, 

 and who do not keep a regular gardener, that the internal ar- 

 rangements of a plant-house, and, above all, the heating arrange- 

 ments, should be so constructed as to be dependent upon the 

 very smallest possible amount of time and attention, and likely 

 to produce the least injury by neglect. 



Among the numerous systems of heating lately applied to 

 horticultural buildings in England, is one called Polmaise, from 

 its having originated at a place in Scotland of that name, the 

 seat of the late Mr. Murray, near Sterling. The principles 

 upon which this method is founded are not new, and the system 

 itself, in other modifications, dates from a period much more 

 remote than any other with which we are acquainted. This 

 system is applied, in a more practical and perfect form, to the 

 warming of many public and private buildings in this country. 

 The very general adoption, however, of this system, does not, in 

 the smallest degree, give us a warrant against its defects. It 



