148 
THE FLORIST’S JOURNAL. 
The mechanical action of charcoal is tw o-fold. In common 
with all similar substances or materials, its admixture with the 
soil renders the latter very perfectly adapted to the free passage 
of moisture through it, and therefore its use tends to prevent 
stagnation of moisture in the soil; besides this, it has rather a 
strong affinity for moisture, and thus it attracts and imbibes a 
considerable proportion during its passage through the soil, and 
becomes a perpetual reservoir to the roots of the plants. It 
parts with this moisture slowly, in proportion as the capillary 
action of the fibrous roots abstract it, and thus it serves to regu¬ 
late and equalise the supply of fluid which is available to the 
roots. It has been hinted, that this v r ater (a compound of 
hydrogen and oxygen) becomes carbonated whilst held by the 
attractive force of the charcoal, and if so, it must be specially 
beneficial to plants, since it would directly supply them with a 
portion of carbon. 
As an adaptation of its mechanical action, I conceive it might 
be advantageously employed in the case of valuable plants, to 
counteract the injuries which frequently result from the interior 
of the ball of earth becoming dry, which, when once the case, 
it becomes almost impossible again to moisten it by any rational 
means. It is my belief that a greater number of valuable plants 
are lost from this cause than from any other. The manner in 
which I think charcoal could be made to remedy this evil, is by 
introducing a few pieces perpendicularly, and extending quite 
through the ball of earth, at each successive shifting, and keep- 
ing them as near the centre as possible ; these could then be 
kept wet by any simple capillary contrivance, and might effec¬ 
tually be made to keep the centre of the soil in a duly and 
regularly moistened state. It would also extend the influence 
of the atmosphere among the roots, as the channels which would 
serve for the passage of water, would, when not so employed, be 
capable of transmitting air. 
Practically I may mention, that I have observed in many cases 
the beneficial influence of charred blocks on the appearance of 
the roots of orchidaceous plants which have been attached to 
them, which is apparent in the more pellucid aspect assumed 
by the growing points. 
April 25. 1844. 
