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On the Homoothtrmal method of Acclimating [Jan. 



Numerous analogies between vegetable and animal life have been 

 observed and dwelt upon, by nearly all writers on vegetable physiology. 

 This knowledge has, however, been but little applied to the advance- 

 ment of horticulture, and not at all to that of agriculture ; so far at 

 least as I yet know : and I think I may with safety assert, that it has 

 never till now been proposed, so to act upon the principle which governs 

 the functions of vegetable life, as to alter entirely the constitution of 

 the plant, and thereby qualify it, though originally from a cold or tem- 

 perate climate, to endure, uninjured, the extreme heats of the tropics. 

 To produce this change is the object of the Hombothermal method of 

 acclimatizing plants : to point out how it may be accomplished, is 

 the purpose of my present communication. 



The effect of cold in preparing plants for forcing, has been long known, 

 and is now constantly employed for that purpose, but the application of 

 heat to seeds during the act of germination, as meaans of enabling them 

 afterwards to resist, uninjured, high temperatures, has never been had 

 recourse to on principle, and but seldom as a chance experiment. Two 

 such experiments, however, have been recently recorded in the Transac- 

 tions of the Agricultural and Horticultural Society of India.* These I 

 shall briefly recapitulate, and then explain the principles on which their 

 respective results may be accounted for, and lastly show their application 

 to the improvement of agriculture, and the acclimating of foreign plants. 

 The following extract, from a report of a Conimittee of the Society of 

 Arts, explains the successive steps of the first of these experiments, 

 conducted by Mr. Anderson, Curator of the Chelsea botanic garden, for 

 the introduction of Joomla rice (a very hardy plant) into England. 

 He was furnished with some seeds of five varieties of hill rice. 

 " They were sown in March, and some of each kind germinated, and 

 did very well while they were kept in the hot-house. In May they 

 were removed to the green-house, where they became stout and healthy 

 plants. In the end of June, they were transferred to a sheltered place 

 in a bason for the growth of aquatic plants, having 9 inches depth of 

 water, and 12 of mud. Here they grew and promised well till the 

 beginning of August, when the weather becoming cloudy and rather 

 cold, they became sickly, and were all dead by the beginning of Sep- 

 tember, without having come into flower. It seems therefore evident, 

 that the temperature even of the warmer parts of England is not 

 sufficient for the cultivation of hill rice." 



The second was made by G. T. F. Speed, Esq. of Calcutta. He 

 " after repeated and disheartening failures with celery and some other 

 English seeds, at last resorted to the plan, almost unthought of in 

 India, of making a hot bed." In this he sowed his seed on the 24th, 



* Vide vol. 3 pages 88 and 89—103, 101 aud 119. 



