SPIRIT OF THE MONTHLIES. 335 



Another tribe of plants are attached to earth, but so slightly that 

 their system of roois is nothing compared with the bulky heads sus- 

 tained ; and as these plants are mostly found on rocks, or on the 

 driest tracts of country, it is evident that the greatest portion of their 

 nutriment is drawn from the atmosphere. Another tribe of curious 

 and beautiful flowering plants is called Epiphytes [or parasitical 

 plants, as the Misleioe], because they attach themselves to the stems 

 and branches of trees, not to sustain themselves by extracting their 

 juices, but to be supported in the deep shade and moist air of thick 

 tropical woods. Some of these are called air plants, and grow as 

 well in a basket without earth, suspended in a warm, damp, shady 

 place, as if they were in their native habitat. 



Thus we see that air is particularly necessary to plants, and as 

 much so to the roots as to the head and foliage ; and it is this fact, 

 as already observed, that justifies all the means of cultivation which 

 we have recourse to with a view of rendering the staple more loose, 

 and consequently more permeable to all atmospheric influences. 



There is one circumstance, however, which deserves to be noticed 

 along with these general remarks : it is this, that all seeds require 

 to be closely embedded in the soil, that is, they should be in close 

 contact with the mould all round ; and, that this should be completely 

 secured, some seeds require to be laid in heavy, as wheat for instance. 

 Now we have only to consider that as the soil has been previously 

 prepared, and more or less reduced to the finest practicable state, a 

 considerable volume of air is incorporated therewith ; and that this 

 air, according to its temperature and the moisture of the soil, facili- 

 tates the germination of the seed, and continues to assist the deve- 

 lopement of the plant. To obtain this close embedding of the seed, 

 it IS the practice to tread it in ; a practice which is foimd of service 

 to wheat, peas, beans, andahnost all small seeds ; but which would 

 be of no avail without the previous disruption and aeration of the 

 soil. 



All these matters premised, it only remains to conclude with a 

 general declaration that, in all our practices and means employed for 

 the amelioration of the land, every thing that can be added or taken 

 away, every operation performed, and every implement used in the 

 culture, should all have for their ultimate object, either directly or 

 indirectly, the breaking up of the compact and impervious surface, 

 so that copious and constant supplies of air may be freely admitted 

 to the roots of the plants. 



