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PART IL 



REVIEWS. 



Art. I. Transactions of the Horticultural Society of London, 

 Vol. VI. Part I. London 1825. 4to. 1 Plate. 

 This part of these transactions consists of eight papers, 

 occupying 108 pages, and ornamented with a coloured folio 

 plate of Marica Sabini. The first paper is on a very im- 

 portant subject, and we shall endeavour to give the essence of 

 it as completely and plainly as possible. 



1. On Climate, considered tvith regard to Horticulture. By John 

 Frederic Daniell, Esq. F.R.S. &c. Read August 17th, 1824. 



Horticulture differs from agriculture by creating artificial 

 climates, and agrees with it in the amelioration of the natural 

 climate ; the first is effected by an inclosed atmosphere in an 

 artificial sructure, and the second by temporary coverings, 

 and other means, in the open air. 



" The basis of the atmosphere has been proved to be of the 

 same chemical composition in all the regions of the globe. All 

 the varieties of climate will therefore be found to depend upon 

 the modifications impressed upon it by light, heat, and moisture, 

 and over these, art has obtained, even in the open air, a greater 

 influence than at first sight would appear to be possible.'' 



Heat is measured by the thermometer ; the intensity and 

 kinds of light have also been measured by some philosophers, 

 but the instrument is not in general use. Moisture is 

 measured by the hygrometer, and the one used by Mr. 

 Daniell, and also in the Horticultural Society's garden, is of his 

 invention, and sold by Mr. Newman in Lisle-street, London, 

 together with the necessary tables and explanations for its 

 use. The range of the thermometer in the shade in the open 

 air in Britain is from 0° to 90° ; in the sun it reaches 135°. 

 The changes of moisture extend from 1,000, or saturation, to, 

 389, or precipitation, the point at which the moisture begins 

 to fall in the form of dew. 



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