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XLVII. On the Effects produced on Vegetation by the 

 Combination of Heat and Moisture, at different Periods of 

 the Year. In a Letter to the Secretary. By Mr. Archi- 

 bald Gorrie, Corresponding Member of the Horticultural 

 Society. 



Read January 17, 1826. 



Sir, 



I may find it no easy task to clear myself of the charge of pre- 

 sumption, in attempting to write, as the title of this Communica- 

 tion would seem to imply, upon a subject similar to that which 

 is treated of by Mr. Daniell, in the first Paper in this volume 

 of the Transactions of the Horticultural Society. I shall 

 only state, in extenuation, that if I had not read that very 

 excellent Paper, and not calculated on the assistance of its 

 distinguished Author, in promoting the investigation sug- 

 gested in this essay, I would not have, at this time, incurred 

 the risk of such an imputation. 



The chief supports of vegetable life are well known to be 

 heat, and moisture ; it may also be added, that light is in- 

 dispensible, but it is to the requisite proportional quantities 

 of the two first that my present observations are intended to 

 apply. To enable the practical Horticulturist to regulate 

 and preserve a proper equilibrium of these elements suitable 

 to the constitution of the plant under culture, he will find 

 many useful and philosophical hints in the Paper above 



