194 ON THE AMOUNT OF MOISTURE ABSORBED BY PLANTS. 



the results of our proceedings will be successful in proportion to their 

 accordance with the economy of vegetation. Hence I would impress 

 upon the minds of amateurs and gardeners in general, the necessity of 

 acquiring some knowledge of, and acting upon, strictly physiological 

 principles. This, and this only, will elevate their pursuits something 

 higher than the mere work of chance, and enable them to calculate 

 with certainty upon the results of their operations. 



My intention is to submit to the readers of the Cabinet, a few 

 popular remarks elucidative of the science of Horticulture. The 

 amount of fluid absorbed by the roots of plants, varies according to 

 the constitution and habits of the species ; the humidity or dryness of 

 the surrounding atmosphere, and also the presence or absence of solar 

 light. Most herbaceous and quick-growing soft-wooded species, 

 require a far greater quantity of moisture to keep them in a healthy 

 condition, than those whose wood is of slower growth, and firmer tex- 

 ture. It would have been difficult to have given a healthy young 

 Vine, Fig-tree, Balsam, Calceolaria, Cockscomb, or Scarlet Pelargo- 

 nium, too much w : ater during the bright dry days of last month 

 (June), whereas an Acacia, Hovea, Eutaxia, Lechenaultia, &c, would 

 have soon become sickly, and died under similar treatment. Now 

 this great difference between the absorbing powers of the former and 

 latter species of plants, results (as above intimated) from their pecu- 

 liar constitution and habits. The rapid growth of the former neces- 

 sarily involves the taking up of a large supply of fluid by the roots, to 

 be converted into nutritious juice ; which conversion is chiefly effected 

 by the leaves under the influence of light. Here by a wonderful pro- 

 cess it is elaborated, the superfluous portion being principally exhaled 

 from their breathing pores (stomata), chiefly situated on their under 

 surface, and the remainder returned (now termed proper juice) for the 

 formation of new tissues, and the consolidation of that already 

 formed. The process of vegetation in the latter tribe of plants is 

 precisely on the same plan, though on a smaller scale ; these roots are 

 less numerous, and have fewer fibrels and sponglets; these breathing 

 pores are also much smaller, and not nearly so many on a given 

 space. Hence it will be perceived, that the small amount of moisture 

 necessary to the support of these, in proportion to such as the 

 former mentioned plants, is owing to their incapacity to dispose of it. 

 So in their culture great care should be taken not to administer a 



