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growth of which will lengthen the radius, while the development of its lateral buds will constitute so many radii around the secondary axis.
The condition of the internal parts is now to be examined. From the point whence the upward growth was resumed to the summit, an exact counterpart of what was found in the stem of the first year exists; but below that point will be found two cones of wood, one overlaping the other, so that a horizontal section exhibits a centre of pith and two zones of wood, exterior to which is the bark; and a close inspection of that will likewise shew that a thin stratum has been added to its internal side. The third year similar phenomena occur, so that there are then three strata of wood at the base, two above, and one at the upper part. Up to this period, and even later, the pith will be in general found precisely in the centre, so as to constitute at once the botanical and mathematical centre of the tree. If, however, the tree have stood in a field or park, so that no external interference, such as the proximity of other trees, as is the case in crowded woods, shall have influenced its development, rendering it difficult in one direction, but easy in another; and if at the end of twenty or twenty-five years a horizontal section of the stem be made, the pith will be found to be eccentric, that is, though still the botanical centre of the stem, it will not be the mathematical centre, owing to the annual strata of wood being thicker on one side than the other. The side of the tree which was exposed to the south and the southeast (in northern latitudes) will be found of considerably greater diameter from the thickness of the zones on that side, than that which faced the north and north-west. The beautiful symmetry which characterised the tree while a sapling is lost, and the branches will be found not only more numerous, but longer on the one side than on the opposite. The superiority in number and length will, in a solitary tree, always be observed to be on the south-east, provided the soil was of uniform quality around the stem. The cause of this must now be explained. The buds of plants, it has been already stated, are stimulated to growth by light; the side exposed to the south-east and south receives a greater amount of light, i. e. not only during a greater number of hours, but generally of a greater intensity; and more buds are therefore developed on that side. The consequence of this is, that more leaves are spread out on the side of the plant where, by the greatest increase of surface, the greatest advantage will accrue to the tree. Thus we find the power which caused the development of the buds, operating to ensure the utmost augmentation of surface where the most beneficial effects will result. This is one among the number of striking instances which the works of creation afford of the end being obtained with the greatest economy of means. More diversified agencies might have been employed, and
the object attained as effectually; but that simplicity, so characteristic of the operations of the Deity, would not have prevailed, to arrest the attention and impress the minds of his intelligent and reflecting creatures.
The condition of the opposite side of the tree merits observation. On it, in the majority of cases, will be found a greater number of cryptogamic or cellular plants, such as mosses, lichens, and jungermannias, than on the other. These plants can vegetate under a fainter light than vascular plants, and flourish best where considerable humidity exists. The northern side of the tree is therefore most suitable for them, and their prevalence on that, in preference to the southern, furnishes a guide not only to the savage when tracking his way through the forest, but travellers have been enabled to regain their lost route in many instances by attending to this sign, which thus served them instead of a compass.
The seed performs its office in supplying the first shoot; all subsequent shoots are derived from buds; their importance is therefore obvious; and it would only be consonant with the general care which is manifest throughout creation to find special provision for insuring their safety, particularly during the winter. Accordingly the buds of deciduous-leaved plants of cold countries are in general wrapped up in certain rudimentary leaves or scales, so folded over the tender point in the centre as to defend it from cold and wet. These scales are always definite in number, and arranged according to a uniform plan, not only in every bud of the same plant or tree, but in every individual of the same species. Their form, position, and number, not only completely encases the important vital part within, but they are frequently coated with a resinous or glutinous and insoluble juice, which renders them impenetrable by rain, and often have a soft down or woolly coating internally, which preserves the warmth of the bud. The buds of the horse-chestnut (Esculus hippocastanum) have both the resinous juice externally and the down within; several poplars, such as Populus balsamifera, willows, &c., are either glutinous or woolly. So long as these scales remain closed, the growing-point is safe, even under a great reduction of temperature; and when the return of warmth in spring stimulates them to action, we uniformly see them "burst their cerements and awake." It deserves to be stated (more especially as one object of these papers is to shew that the utmost precision is displayed in the organisation of plants), that each kind of tree has a definite number of scales in every bud, and that the shoot which results from the development of all of them never possesses beyond a certain maximum of internodes. Thus, the ash (Fraxinus excelsior) has in each bud two pairs of scales, five pairs of leaves, and, at the utmost, three internodes in each shoot of the same year; the horse-chestnut has seven pairs of scales, five pairs of leaves, and five internodes; the Acer campestre (or field-maple), six pairs of scales, five pairs of leaves, and ten internodes; the Sorbus (pyrus) aucuparia, three pairs of scales, five pairs of leaves, and eight internodes.†
the increase being horizontal more than perpendicular,
which gives them a definite shape, and renders them
It is impossible for the European to imagine the effect on the scenery of these chiefs of the vegetable kingdom, whether they grow in masses, or present solitary stems towering above the other mighty trees of the equinoctial regions. The foliage is often of the same gigantic character as the stem, and one trunk, with its majestic crown of leaves, affords shade and shelter to the weary traveller sinking under the scorching sunbeams, which yet are the means of bringing to perfection these gorgeous attributes of tropical climes.
The fluids which, collected by the roots, permeate the more superficial layers of exogenous plants, especially of the leaves, would escape by the rapid evaporation, were it not for an arrangement which requires to be noticed here. Organised structures differ from unorganised, which are mostly angular, and of uniform composition externally and internally, by having an external envelope or covering,
See La Description de l'Egypte; ou, Recueil des Observations et des Recherches qui ont été faites en Egypte, pendant l'Expédition de l'Armée Français. Planches. Histoire Naturelle, tom. deuxième, Bis. Botanique, par M. Delile, Planche 1. Palmier Doum.
"Those blazing suns that dart a downward ray,
"Palms," says Martius (the distinguished traveller and illustrator of this order of plants), "the splendid offspring of the earth and the sun, chiefly acknowledge as their native land those happy regions where the beams of the latter for ever shine. Inhabitants of either world, they hardly range beyond 350 in the southern, or 400 in the northern hemisphere."
"While some," observes Humboldt, "have trunks as slender as the graceful reed, or longer than the longest cable, others are three or even five feet thick; while some grow collected in groups, others singly dart their slender trunks into the air; while some have a low trunk, others exhibit, such as the Ceroxylon andicola, a towering stem 160 to 180 feet high; and while one part flourishes in the low valleys of the tropics, or on the declivities of the lower mountains, to the elevation of 900 feet, another part consists of mountaineers bordering upon the limits of perpetual snows."
The epidermis is well contrived to hinder excessive evaporation, being destitute of pores (or stomata). It likewise prevents the penetration of external moisture, which would occasion the decay or putrefaction of the subjacent tissues. The earthy and often flinty (siliceous) nature of this part helps to ensure this object. Many plants, particularly the equiseta (or horse-tails, Dutch rushes), contain a great quantity of silex, forming a regular coat under the cuticle, so that by slow maceration in water the vegetable matter may be removed, and a tube or perfect cylinder of siliceous crystals remains. The large proportion of silex in the stems of grasses, such as bamboos and the cereal plants, aids also in keeping them erect, notwithstanding the weighty head of grain they have to support.
The bark, moreover, abounds with carbon, or charcoal, which strongly resists the tendency to putrefaction. The bark of the birch has as much as 62, and that of the cork-tree 64 per cent of carbon, which is at least 10 per cent more than any wood yet examined is known to possess. Hence the bark of trees which have been felled, and allowed to lie in humid places, often remains entire after the central part has mouldered away. So thoroughly, indeed, in a growing tree, does the bark prevent the destruction of the sub
An imitation of the natural protecting covering of plants is attempted to be bestowed on stakes and piles, which are intended to be driven into the earth, by previously charring them. And when the branch of a tree is lopped off, a substitute for the epidermis is had recourse to, in order to preserve the remaining portion of the tree, by covering the cut surface with a sheet of lead, or coating of paint,-expedients far short in efficacy of the original, which has been aptly designated by Sir J. E. Smith as "a fine but essential barrier between life and destruction."
jacent structures, that upon the death either of a branch or of an entire tree, when it becomes an object with nature to hasten its decomposition, that its elements may be again turned to use, the removal or at least the breaking up of the epidermis is one of the first steps in the process. This is accomplished in a very singular and interesting way. Various fungi (or minute mushrooms) develop themselves under the epidermis, and, by increasing in size, either perforate it by several small points, according to their form, or cause it to give way extensively, and separate in large portions. Many plants have peculiar fungi attached to them, which only appear when the death of the plant, or some part of it, is impending. These facilitate the decay of the original structures, not only by appropriating to themselves the nutritive juices, which are immediately under the bark, but by permitting the escape of the vital fluids (the blood, as it might be figuratively termed) of the plant, such as the gummy or saccharine liquids of trees. Thus the kind of gum which exudes from the stems of plum and cherry trees, makes its escape through openings effected in the bark by a fungus which passes from within outwards, after the fashion of a screw, and called Nemaspora crocea. So long, however, as the integrity of the bark is preserved, the juices essential to the growth of the tree are retained within it.
Further, the epidermis in many cases prevents the frost injuring the bark and internal parts of the tree. This is most manifest in trees which have numerous layers of epidermis. Not only is the carbon, which has been stated to abound in the bark, a very bad conductor of caloric, serving the double purpose of confining the internal heat in winter, and excluding the external heat in summer, but likewise a layer of air is retained captive between each layer of epidermis, which thus form as it were so many coats, and pre- | vent the establishment of an equilibrium of temperature between the interior of the tree and the surrounding atmosphere, which, if very low, would freeze the juices, or, if very high, would, by over-exciting the actions of the plant, induce exhaustion-states alike prejudicial, and, when in extremes, fatal. A peculiar appropriateness will generally be discovered between the number and texture of the epidermal layers, and the place of growth of the plant. Thus the birch (Betula alba), which, of all European trees, has the greatest number of layers of the epidermis, is also the one which approaches nearest to the snowy summits of the Alps, and extends farthest towards the icy regions of the pole. Specimens of the Abies (pinus) Douglassii have been found with an epidermis nearly two feet in thickness. This tree forms immense forests in N. W. America, between 43° to 52° N. lat. In South America a very remarkable tree is mentioned by Don Ulloa, under the name of quinales, as having about 300 epidermal layers; and several trees in New Holland have barks with layers scarcely less
Nor is it merely by these means that the bark is enabled to impart security to the inner structures, since in several instances the superficial layers have
• One species (of Leptospermum) was remarkable for its bark, which was about an inch thick, and composed of a great number of flakes, lying one over another, very easily separable, and as thin as the finest Chinese paper. This singular organisation of the bark occurs only in New Holland: it is nearly the same in the Eucalyptus resinifera; and I had observed it also on the south-west coast of this country, on two large trees, one belonging to the family of Proteacea, the other to the Myrtacea.LABILLARDIERE's Voyage in search of La Perouse, p. 284. London, 1800.
The strata of the bark are in general finer, even in the same species of plant or tree, when growing in cold regions. Thus the layers of bark of the Tilia europaa, or lime-tree, are softer and of closer texture when produced in Russia and Sweden than in Britain, and are therefore preferred by gardeners for matting; just as the fur of animals inhabiting northern countries is softer and denser than those of warm regions, and consequently employed for winter-clothing.
the power of secreting materials which conduce in various ways to the object proposed. The leaves and green parts of the stem of many plants, particularly such as grow along the sea-coast, are observed to be covered with a fine coating of a bluish-green colour (on which account they are termed glaucous), and which is of a waxy or resinous nature, and therefore neither soluble in water, by which it could be washed away by rain, nor easily penetrated by the moisture more or less present in the air surrounding the plant. The same delicate coating forms the bloom seen on many smooth-skinned fruits, such as plums, nectarines, and apples, and which, when once rubbed off, is never renewed by the leaves, though it is so by the fruits before they are ripe. It constitutes an important protection against the injurious effects of the spray of the ocean to some plants, such as the yellow-horned poppy (Glaucium flavum), and the cabbage (Brassica oleracea), which is originally native of the cliffs on the coast, and which has retained the power of forming this secretion even when growing in gardens far inland. Fruits are likewise protected against the absorption of water from the atmosphere, not only when growing, the introduction of which into their tissues would interfere with their ripening and diminish their flavour, but also aids greatly in the preservation of the fruit when plucked, if it be intended to keep them. The bloom should therefore never be wiped off the surface of apples which are wished for winter-use, but, on the contrary, carefully retained, by the most cautious handling of them.
The wax-palm of the Andes (Ceroxylon andicola),which inhabits the side of the mountain called Quindiu, in lat. 4o 35" north, occupying a zone from the height of 7538 to 9843 feet above the level of the sea, and where the mean temperature varies from 52° to 64°, according to its height, thus soaring far above the usual locality of its kindred, which rarely exceed 3000 feet, is exposed to a degree of cold unknown to the others, and consequently to the deposition on its surface of a quantity of moisture, which would be extremely pernicious, were it not protected by a natural covering of a most efficient kind. The stems of this palm, which are often 150 to 160 feet tall, are coated with a varnish of wax and resin, so thick that it can be scraped off, and which effectually defends the inner portion from wet. "And if," as observes Bonpland, "it be a phenomenon to find a palm growing at the height mentioned, it is much more wonderful that there should exude from it a mixture of wax and resin. This substance, extremely inflammable, which covers all the plant, is the produce of a vegetable juice as insipid and as watery as that which is obtained from the trunk of the cocoa-palm." It cousists of two-thirds of resin and one-third of wax. Where the leaves have fallen off, and where the internal tissues would be exposed, the coat of wax is often about a quarter of an inch in thickness; and as this part has not the power of secreting the compound, it must have flowed from the entire surface immediately above, and so formed a shield against the atmosphere over the wounded portion, which it completely seals.
The arrangements for the protection of aquatic plants are equally remarkable. However necessary a certain quantity of water may be to the well-being and exercise of the functions of a plant, an excess of it is destructive; and to prevent such a casualty, plants which grow under water, and which are devoid of cuticle (though all parts of such plants as rise above the surface are provided with that coat), are surrounded with a glairy liquid, which not only facilitates their movements in the water, and prevents the stem or foliage from being broken by the agitation of the waves, but actually hinders the water from coming in immediate contact with the tissues of the plant. If the flower or leaf-stalk of the water-lily, or any similar plant, be taken up, it can be drawn through the hand
with the greatest ease, being covered with this lubricating material. All aquatic animals, even frogs, have an analogous secretion. The spawn of the frog is preserved against the dissolving power of the water by the like external envelope; and the feathers of swans, ducks, and sea-fowl, have an oily coating over them, which not only keeps them from being saturated with moisture, but enables them to dive with greater facility. In all these winged creatures the sebaceous glands near the surface are of unusually large size.
The stems of plants thus protected progressively extend into the medium in which they are intended to exist for a time; and there unfolding their leaves, which are annual thin expansions of the bark, they exercise an influence on the atmosphere of a most important kind, while they are in turn influenced by that fluid, their reciprocal actions producing the most beneficial results. The length to which the explanation of the mere structure of the stem has proceeded, renders it impossible to detail on the present occasion even a few of the useful effects which flow from the harmonious interchange of their properties, the one gaining in solidity, and the other in purity and fitness for the respiration of animals. These I must reserve for the following paper; only observing at present, that the exposition of them will lead every humble investigator to the conclusion, that they could only have been contrived, as they are maintained in order and perfection, by Him of whom it has been said, "He doeth all things well."
LIFE OF REV. H. SCOUGAL.
Ir is the mark of wisdom to know what are the duties to which each particular relation in life calls us, and to address ourselves to those duties. Mr. Scougal possessed this faculty, When he became a professor in the university of which he had been so lately a student, he shewed that "even in this station, 'to him to live was Christ."" Conscientious in all that he undertook, he strove so to behave himself, that he might not only have the satisfaction of knowing that he had done right in each stage of his duties, but he was anxious also to gain the esteem of the youths. This he accomplished by a union of freeness and authority in his intercourse with them. He never had any separate interests of his own; nor did he foment any of those misunderstandings which will spring up in every society of persons; but he always tried to allay and settle them; and when he could not accomplish this, he stood aloof. He was quite uncorrupt in respect of gain, as he shewed when on one occasion some disorderly conduct had been committed by his pupils, for which they were sentenced to pay a fine, and give assurance of their future good conduct. The proud spirits of those young men would not permit them to consent to the payment of the fine; but if Scougal had chosen to have paid it in their name, the matter might have ended. But, kind as he was, he would not be a party to such a transaction, which would have been a connivance at misdemeanour, and would have offered a premium for the commission of offence. The youths were expelled for holding out in their refusal, though their departure was a serious loss to Mr. Scougal's income, as but few were left behind.
One of the principal studies to which he directed the
minds of his pupils was natural philosophy; for he felt that it would give them enlarged notions of God, to consider his immensely grand works, and the marks of design exhibited by the very smallest creatures. He had another aim in directing them to this class of studies, besides the intrinsic worth of the studies themselves: he wished to take them off from a disputatious, wordy philosophy, and from the conceit of being able to skirmish with the mere terms of an ambitious phi
losophy, while the principles of solid truth were unknown. He used to employ the evenings of the Lord's day in pious conversation; and he would talk privately with the students, according to the case of each. The ill-disposed he would warn; and where he saw in any the buddings of what was good, he would cherish the opening grace.
When, after due deliberation, Mr. Scougal had entered into holy orders, he was stationed, by God's providence, at Auchterless, a small village about twenty miles from Aberdeen. His stay here was destined to be short; but during it, he gave abundant proofs of his fitness for, and his zeal in, that holy function he had undertaken. He was extremely circumspect in his personal conduct, that his "good might not be evil spoken of," and that no hinderance might arise to the work of his Master from himself. Catechising was a branch of the minister's duty, of which he both felt the necessity, and discharged it with the utmost effect. He was very plain and affectionate in his catechetical teaching; and he found, as many other pastors have done, that parents may be obliquely reached through the instruction which is expressly directed to their children. He took pains to study the dispositions of the people, and adapted himself to each as he found it; and wherever he saw a spark of goodness, he was cheered and encouraged. He endeavoured to bring his people into the habit of attending public worship in good time, because he had a sense in his own mind, not only of the decorum, but of the privilege attaching to an early resort to the Church-service; "thinking it very unfit that the invocation of Almighty God, the reading of some portion of the holy Scriptures, making a confession of our Christian faith, and rehearsing the ten commandments, should be looked upon only as a præludium for ushering in the people to the Church, and the minister to the pulpit." Scougal felt that God's house is a "house of prayer;" and though preaching, as a divine ordinance, is added to worship, it can never be regarded as the principal object for "assembling ourselves together." It is neither expedient nor lawful to draw comparisons between prayer and preaching, to represent one as "more important" than another. Both are to be used, for both are of God's appointment: but since the service of the Church is constructed upon an orderly principle, that notion will be violated (if it ever has been learned,) by those who make a habit of entering the Church when the service has begun. Mr. Scougal's preaching has been thus particularly described by the friend who drew the picture of his character at his funeral :—" A wise man hath lately written an essay how to make a good use of bad sermons: and it were to be wished we were instructed in making good ones; such I mean as might have an influence on men's hearts and lives. And sure I think all that heard him will acknowledge
his practice to be no contemptible pattern. He thought that it should be a minister's care to choose seasonable and useful subjects, such as might instruct the people's minds, and better their lives, not to entertain them with debates and strifes, of words;-that he should express himself in the most plain and affectionate manner; not in airy and fanciful words, nor in words too big with sense, which the people's understanding cannot reach; nor in philosophical terms and expressions, which are not familiar to vulgar understandings; nor in making use of an unusual word where there could be found one more plain and ordinary to express the thought as fully. He looked upon it as a most useful help to make the Sunday's sermon the subject❘ of our meditation and mental prayer for the foregoing week, that it may thereby sink deep into our own spirits, and affect our hearts, which would make us more capable of teaching others. He thought it a fit expedient for composing us to a serious and affectionate preaching, to propose to ourselves, in the meditation of it, purely the glory of God and the good of men's souls, and to have this always in our eye. And how conformable was his practice to these rules! The matter of his discourses was always so useful and seasonable; his words and expressions so plain and well chosen. I cannot here omit the deep sense he had of true eloquence, professing he would give all the other human learning in exchange for it: and he judged there were two essential defects in our best kind of eloquence; the one was, that we did not enough reflect upon the temper of the persons we were to speak to, and what kind of words and expressions would make the best impression upon their minds, and therefore it was nothing strange that words let fly at random touched them so little. The other, that our
hearts were not thoroughly endued with those dis
positions we would work on others by our words, and therefore it was no wonder all we said made so little impression on them."
The history of Scougal is not filled with events; what has been recorded of him is rather a delineation of his character, than a lengthened account of important occurrences. We are accordingly now introduced to the last period of his life. He had ministered at Auchterless but one year, when he was called to Aberdeen, and promoted to the professorship of divinity in King's College there, though not more than twentyfour years old, obtaining that appointment, not by a contested election, but with the unanimous voice of the clergy of the diocese, who choose the professor. So modest was he, that he would not consent to accept
the office as soon as he was elected, but took until the next meeting of the clergy to deliberate upon the
He entered upon its duties, feeling that "all his sufficiency was of God," and fulfilled them with an
assiduity and an efficiency not to be surpassed. He who had "delighted to honour" this young man of
such rare excellence, now thought fit to confer upon him unfading distinction among the ranks of the blessed saints in glory. In his twenty-seventh year "he fell into a consumption, which wasted him by slow degrees, and put an end to his valuable life on the 13th of June, 1678. He was buried in King's College church, Old Aberdeen; and a Latin inscription, in the following terms, was put upon his tomb:
Sacred to the memory of
Son of the Right Reverend Father in Christ, PATRICK, Bishop of Aberdeen:
For four years Professor of Philosophy in this Royal University,
Pastor of the Church in Auchterless.
And deposited here his mortal remains.
His works are, 1. The Life of God in the Soul of Man. 2. Nine Discourses on important subjects. 3. Occasional Reflections, and Moral Essays, written while he was a student at the university. 4. Three manuscripts in Latin, viz. A short System of Ethics, or Moral Philosophy; A Preservative against the Artifices of the Roman Missionaries; and, a Treatise of the Pastoral Care-the last unfinished.
SUPPORT AND PROTECTION IN THE DAY OF TRIAL:
BY THE REV. EDWARD EDWARDS, Curate of Wrexham; and formerly Perpetual Curate of Marsden.
ISAIAH, xliii. 2.
"When thou passest through the waters, I will be with thee; and through the rivers, they shall not overflow thee: when thou walkest through the fire, thou shalt not be burned, neither shall the flame kindle upon thee."
IN the holy Scriptures threatenings of deserved wrath, and promises of undeserved blessings, are intermingled ;-the threatenings to excite in us salutary fears, the promises to inspire us with hope. Of this wise intermixture, the text, viewed in connexion with the close of the last chapter, is an instance. From the 22d verse to the end of the 42d chapter, there is a prediction of punishment to be inflicted on the nation of Israel for its repeated sins and provocations, and especially that crowning sin, the rejecting of the Messiah. Of this sin that nation would at last be guilty, and this would fill up the measure of Divine wrath to be poured out on God's ancient people. This sin-the rejection of Christ is the most aggravating of all sins, and surely seals the final damnation of an individual or a people. For if you reject Christ, whether by practice or profession, you reject the only remedy which the great God of heaven and earth hath provided for a ruined world—a world lying in iniquity; if you reject Christ as your Saviour,
"there remaineth no more sacrifice for sin." The prediction of wrath against Israel, as contained in the latter part of the last chapter, is succeeded by very rich and consoling promises in the text, which comes in here just