KIDD'S OWN JOURNAL. 



15 



mode of subsistence of the vegetable, and 

 almost the first property necessary for its 

 life, is the power of absorbing the needful 

 constituents of its being from the surrounding 

 elements. It is, accordingly, provided with a 

 root by which it takes hold of the soil, and 

 by the direct agency of which it is fed. 



A distinguished botanist has indeed aptly 

 defined a plant as " a living body deprived of 

 sensation or power of moving from place to 

 place, and fed by means of external roots." 

 With these it imbibes from the soil in which 

 it is placed, the needful fluid or sap by which 

 it is sustained ; and by this apparently simple 

 apparatus the whole important and compli- 

 cated chemical processes are carried on, and 

 the crude soil converted into the needful 

 constituents of vegetable matter. The 

 elementary bodies which form the essential 

 constituents of sap are — carbon, oxygen, 

 hydrogen, and nitrogen. These combine and 

 form various secondary bodies, in which state 

 they are most frequently absorbed by the 

 plants. For this purpose, the root possesses 

 certain structural characteristics, adapting it 

 to its peculiar functions. The ramifications 

 are irregular, differing in this respect from 

 the symmetrical arrangement of the branches. 

 The smaller divisions, or fibrils, as they are 

 called, consist of little bundles of ducts, or 

 spiral vessels, surrounded by woody fibres, 

 lying in a mass of cellular tissue. Towards 

 the point of these fibrils the tissue is loose, 

 and the outer covering wanting ; so that they 

 rapidly absorb the fluid with which they are 

 surrounded and brought in contact. 



Roots are divisible into various classes, 

 according to their form, mode of develop- 

 ment, duration, &c. ; but the purpose of all is 

 the same. They receive and re-adapt the 

 food necessary for the sustenance of the 

 plant : digesting it, and converting it, with 

 the needful aid of light and heat, into the 

 healthy sap or vegetable blood which circu- 

 lates through the veins of the living plant. 

 Adapted as they are also for attaching the 

 plant to the soil, they exhibit all the diversity 

 which pertains to lowly shrubs or plants, and 

 tall umbrageous trees ; the one having only 

 its tender rooty fibres, terminating with the 

 spongioles or special organs for reception of 

 nutritious moisture, while the other are pro- 

 vided with ingeniously-adapted and widely- 

 branching roots, capable of taking firm hold 

 of the ground, and resisting the tremendous 

 force with which the tempest assails the 

 trees of the forest. This latter character 

 peculiarly pertains to plants, as living bodies 

 destitute of the power of moving from place 

 to place. 



In other respects, however, the roots 

 supply the same functions in the plant as 

 the absorbent vessels do in the animal. The 

 organs of absorption are, indeed, very dif- 



ferently situated in the two ; the animal 

 deriving its nutriment from the stomach — an 

 internal reservoir, into which it has previously 

 introduced the needful and most select ele- 

 ments of nourishment ; while the vegetable 

 organs of absorption act exclusively on the 

 external soil. They do not, however, receive 

 all with which they are brought in contact ; 

 but select and reject, with a discrimination 

 not less wisely adapted to their requirements 

 than the instincts of the ower animals. 



The power of absorption by the roots of 

 plants has been explained to be due to the 

 capillarity of the cellular tissues of which 

 they are composed. Such an explanation, 

 however, is so far as it seems to~ indicate a 

 mere mechanical process, cannot satisfy the 

 mind; for the process goes on healthily 

 during the life of the plant, but no sooner 

 does vitality cease, from whatever cause, than 

 these fine capillary tubes, which had acted 

 with such seeming mechanical regularity 

 before, altogether fail — and the dead plant 

 retains its wonderful contrivances of tissues, 

 fibrils, spongelets, cells, pores, and sap 

 vessels, to as little purpose as the human 

 body is possessed of all its wondrous ana- 

 tomy, when the spirit has fled away. 



The living principle thus present in the 

 plant, and quickened into activity with the 

 returning warmth of spring, exhibits a vital 

 activity closely allied in some respects to 

 that of animals, though in others altogether 

 different : and especially in that retention of 

 the vital principle under certain conditions, 

 as when grain is laid by, or seeds are buried 

 in the ground so deep as to be beyond the 

 reach of light and air. In this way, also, the 

 winter frosts serve to keep the seeds of the 

 previous autumn in a dormant state until 

 the returning warmth of spring sets them free, 

 and, under the genial influence of the warm 

 moisture and porous soil, they germinate, 

 and shoot up into stem and leaf. Here, how- 

 ever, we see one distinct line of argument 

 presenting itself to our mind, the force of 

 which it is impossible to gainsay or resist. 

 The gardener or husbandman, by soils and 

 manures, by draining or forcing, — or, again, 

 by grafting, transplanting, and training, can 

 work many marvellous changes on plants, 

 flowers, and fruit ; but the original mystery 

 of vegetable life — the vital principle without 

 which all else is vain — remains as mysterious 

 and inexplicable as ever. 



Reason as philosophy may — by means of 

 all the lights of science, and all the wonder- 

 ful and mysterious laws which modern dis- 

 coveries have revealed — we are still brought 

 back to the simple argument of a child, which 

 intuitively discerns the necessity of a first 

 cause, and finds ample satisfaction in the as- 

 surance that God made all these things — 

 that He said, " Let it Z>e/" and it was so. 



