378 First Report on the Experiments carried on 



tires will be able to maintain such a temperature as is 

 requisite* The only weather which was sufficiently severe 

 to produce any perceptible effect upon the plants inside either 

 these houses, was in the beginning of 1823, a few months 

 after they were built. At that time, the thermometer was 

 not at any time in the open air more than a very few degrees 

 below the freezing point ; but this slight degree of cold was 

 accompanied with a strong north wind; and then it was found 

 impossible to keep the frost out of the north house without 

 covering the outside with mats. At that time however the 

 laps of the glass were not puttied, which made the external 

 covering necessary. The remedy of closing the laps with 

 putty, was immediately and successfully applied. It must 

 not be forgotten, that the above remarks apply to Curvilinear 

 Stoves only ; with respect to Green-houses constructed with 

 iron, the Garden of the Society at present affords no evidence. 



Forcing Houses In the Experimental Fruit and Kitchen 

 Garden, two small Glazed-houses have been erected, the one 

 a Curvilinear Iron-house, the other a wooden Peach-house. 



Peach-house. No observation can be made respecting 

 this house until the trees, with which it is planted, shall have 

 arrived at ji bearing state. It is constructed more for the 

 purpose of exhibiting and comparing varieties of the Peach 

 and Nectarine, than for the production of early or large crops. 



Curvilinear Fruiting-house. Upon this house several ob- 

 servations have been made which deserve attention. It was 

 contrived for the purpose of forcing fruits in pots. In its 

 internal arrangement, it is somewhat the same as the south 



* February, 1826. The experience of the past winter has fully justified this 



