292 



On the Homoo thermal method of Acclimating [April 



If the premises, on winch my views are grounded are correct, plants 

 so prepared should be not only endowed , with the power of resisting 

 high temperature, but should produce seeds endowed with similar 

 properties, and become the means of greatly extending our catalogue 

 of useful plants : nor need the use of glazed cases be confined to the 

 introduction of extra-tropical plants ; those from other tropical coun- 

 tries might in like manner be introduced with certainty, and without 

 loss or accidents on the voyage, from bad weather, exposure to sea 

 spray, changes of temperature, &c. and could be kept in safety after 

 landing, till a favourable season arrived for transplanting them ; or, 

 should it be desirable or necessary to send them into the interior, the 

 continued protection would be equally effective for their preservation. 

 On this part of the subject I believe it is quite unnecessary to say 

 more, as the application must be obvious to every one. 



The cases consist of a box, the joinings of which are made water 

 tight, to retain the moisture of the earth. To this a glazed frame is 

 fitted, so close as just to go easily within the box. The frame ought 

 to be about 18 inches or two feet high. The soil being then well 

 moistened and the plants introduced, the glazed frame is fitted on, after 

 which nothing further is required. Mr. Ward observes — " It may be 

 as well to state once for all, that the success of my plan is in exact 

 proportion to the admission of light to all parts of the growing plants, 

 and to the due regulation of the humidity of the mould, wherein they 

 grow. It is safer in all instances to give rather too little than too much 

 water. Plants frequenting a humid soil require more water, while 

 fleshy succulent plants are best preserved, planted in dry sand." 



The French memoir has for its object the determination of a point 

 of the highest importance to the tropical agriculturist, and one, which 

 it is surprising has not hitherto been investigated with the care which 

 it obviously merits, namely the highest temperature at which the more 

 common European Cerealiee can be cultivated with success ; and, so far 

 as it goes, is one of great value. Reasoning from insufficient data, I 

 was led to infer, that seeds, sprouted in a high heat, would pro- 

 duce plants capable of successfully resisting temperature, much higher 

 than those to which they are generally exposed in the usual course of 

 cultivation, and thai in this way extra-tropical plants might, so to speak, 

 be tropicalized. The experiments of the French philosophers unfor- 

 tunately do not bear on this point, but as it seems desirable that the 

 result, as well as their deductions, should be known among us, I shall 

 give a brief summary of them, and then show the points in which they 

 appear to me defective, in the hope that the ingenious authors may be 

 induced to repeat them, with such modifications as may tend to confirm 

 or refute my views. 



