INTRODUCTION. 31 



surcharged with it ; but soon as the sun's heat 

 increases evaporation, or should sweeping winds 

 prevail, the scent is dispersed far and wide. 



A curious circumstance, lately noticed, shows 

 that the fragrance of flowers is capable of being 

 exalted by qualities placed, or which happen to 

 be, in the near neighbourhood. Onions growing 

 near roses improve their scent. This seems to 

 be a proof that there is an intro-susception of 

 the extraneous quality ; and, moreover, confirms 

 the old idea, that strong or pungent applications 

 to the roots exalt, not only the colour, but the 

 scent also. 



It has been noticed, of the common ever- 

 flowering Chinese rose, that, when first introduced, 

 about 1793, it was, as the little darker- red one 

 still is, almost scentless ; though now, 1829, with 

 many of its varieties, highly fragrant. 



OF SOILS 



The surface of our planet is composed of 

 various descriptions of matter, all arranged and 



