PRINCIPLES OF ACCUMULATIVE POTTING. 
131 
attended the adoption of that principle : we are fully aware, that 
the chief source from whence plants derive their food is from the 
soil (it containing the necessary elements), by the aid of water, 
and that this important part of vegetable economy may be under¬ 
stood, I shall proceed to an humble attempt of an explanation of 
the spongiole, which takes up the food for the maintenance of 
vital action. By an inquiry into the nature of such, we should 
readily see the beneficial effects which must result to the ma¬ 
jority of plants from adopting that system. We are informed by 
botanists from microscopical investigations, that each of these 
spongioles has an important office to discharge ; their cellular 
tissues holding carbonic acid in solution, the ducts convey the 
fluid, while the spiral vessels charged with oxygen take it up for 
the support of the plant: it must then be obvious to all, that an 
obstruction, in checking the action or reaction of the spongiole, 
must tend to produce injurious effects, though ever so minute. 
In the removal of a plant from one pot to another, it is found, 
provided the plant is in good health, that the roots are adhering 
to the pots, and compressed from the confined space. It is then 
evident, in the constant repotting of a plant, it must be pro¬ 
ductive of injurious effects, by tending to disturb the action or 
crush the vessels of the spongiole. If such take place, it must 
require time to regain its former vigour. Should the plant have 
been in a flourishing state, the leaves will soon exhibit signs of 
the evil: thus, in order to supply the waste which arises from the 
emission of oxygen, or evaporation which takes place in the 
leaves, an over-supply of water is resorted to, and the earth in 
many cases becomes soddened, though the drainage may be 
good, the spongioles from this check being unable to take up the 
necessary fluid. 
With those plants which have to acquire a large amount of 
growth in a given space of time the evil must be still greater, as 
in the Balsam and other tender annuals ; and this tends to retard 
their growth, producing premature flowering. It has been 
argued, that in applying so great a body of earth to a plant, 
which requires a length of time before its root can occupy the 
space allowed, the soil may become impure from the repeated 
application of water: this must depend on the drainage, or the 
state of the pot. Though the spongioles are deprived of light, 
yet the admission of atmospheric air is necessary for their well¬ 
doing, as may be plainly seen by their intermixing with the 
