they will be chemically combined. A more lengthened and difficult process will be requisite to separate these two substances, and exhibit them in their original forms. In order to combine any two or more substances, it is generally necessary (unless heat be applied) that one of them should be a fluid. The reason of this is obvious, if we consider, that before a union between them can be effected, the force of cohesion must be overcome; and it is impossible, by reducing a solid substance to the finest powder, to produce a separation of the ultimate atoms, or most minute particles, that compose it; and the attraction of cohesion is sufficient, in many instances, to overcome the influence of the attraction of affinity. force is found to operate. Affinity may exist, but not sufficiently strong for combination. Many ingenious attempts have been made by chemists, to determine the precise degrees of intensity in which this attractive power is to be found. In order to obtain an extensive and thorough acquaintance with the changes that take place in the properties of bodies, it is of the greatest importance to learn the strength of affinity between them. To assist in this acquisition, tables of affinity have been prepared by eminent chemists, which have proved of extensive utility. The plan adopted in these tables is, to place at the head of a column the name of the substance whose affinities are required; and below it, the names of the bodies that have In some cases of chemical union, the pe- an attraction for it, according to the culiar properties of the different substances power they possess. Thus, under the brought together are in a great degree pre-term acetous acid, or vinegar, there would served; in others, the most remarkable follow successively, barytes, potash, soda, effects are produced. Iron and tin are both strontites, lime, ammonia, magnesia, allumalleable and ductile metals; but when mina. S. melted together, the compound body that is produced, is of a very brittle nature. By the mixture of different metals, changes are ANECDOTE OF A NEGRO. dated Hampton, 1782. "THE other morning the captain of one of Commodore Johnson's Dutch prizes break fasted at Sir Charles Middleton's, and related the following little anecdote: also produced in regard to weight, sound, Letter from Miss H. More to her sister, and colour. It is a striking consideration, and a surprising evidence of the wisdom and goodness of God, that some of the most useful and necessary substances in nature, are composed of elements which, combined in different proportions, constitute bodies of the most formidable and destructive cha--One day he went out of his own ship to racter. Water, so mild and agreeable in its nature, and so essential to human existence and comfort, is composed of oxygen and hydrogen, or inflammable air: the common salt, so wholesome and used in so many ways, is formed of two ingredients, either of which, if taken into the stomach alone, would produce instant death: they are called sodium and chlorine. Can we not here most clearly discern the hand of an all-wise Disposer, who, rich in goodness, directs all the combinations of matter, for the convenience and well-being of his creatures? Numberless instances might be adduced wherein the properties of compound bodies are entirely distinct from, and opposed to, the original simple bodies of which they are formed; but a very few illustrations of this kind can be introduced into so brief and general an outline of chemistry. The attraction of affinity never exists between two bodies of the same kind. Iron has no chemical attraction for iron, nor mercury for mercury. There are also different degrees of intensity in which this dine on board another: while he was there, a storm arose, which, in a short time, made an entire wreck of his own ship, to which it was impossible for him to return. He had left on board two little boys, one four, the other five years old, under the care of a poor black servant. The people struggled to get out of the sinking ship into a large boat, and the poor black took his two little children, tied them into a bag, and put in a little pot of sweetmeats for them, and put them into the boat; the boat by this time was quite full; the black was stepping into it himself, but was told by the master there was no room for him, that either he or the children must perish, for the weight of both would sink the boat. The exalted, heroic negro did not hesitate a moment. 'Very well,' said he, 'give my duty to my master, and tell him I beg pardon for all my faults.' And then, guess the rest, plunged to the bottom, never to rise again, till the sea shall give up her dead. I told it the other day to Lord Monboddo, who fairly burst into tears. The greatest lady in this land wants me to make an elegy of it, but it is above poetry." This touching account of the devotedness of a poor negro to his master, may remind us of that passage in holy writ, Rom. v. 7, 8, in which the inspired apostle says, "For scarcely for a righteous man will one die; yet peradventure for a good man some would even dare to die. But God commendeth his love towards us, in that, while we were yet sinners, Christ died for us." The nobleman, mentioned above, burst into tears at the recital of this touching anecdote; how few are duly sensible of the far surpassing love of God towards us rebellious sinners, in giving his only begotten Son Jesus Christ to die for us! There are a few terms which constantly recur in describing the parts of a flower, that it will be useful for the convenience of the reader to explain, before we begin to treat of those orders or families under which it has been found desirable to place all plants which have a certain well-defined relationship to each other. We recommend our readers to obtain a clear knowledge of these terms, that they may be prepared to enter on the study, and may comprehend our future references. A little pains at first will save much future trouble. In the above representation of the percedanum officinale, or hog's fennel, a plant very common in salt marshes, the principal parts of a flower are pointed out by the small letters. Figure 1, a. is the peduncle or fruitstalk, upon which the flower is supported. b. The petal or coloured leaf, forming a part of the corolla, or most conspicuous portion of a flower. c. Is named the lappet, into which each of these petals is lengthened. This small tongue, or lappet, which is folded back upon the petal, gives a remarkable character to many plants of the umbelliferæ order. d. Is the filament, and is one of those slender threads, which support a little yellow head, called an anther, at e. The filament and anther together is called a stamen. g. Is the germen, by which name the unripe fruit is always known among botanists. f. Is the style, a small stem in which the germen always terminates. The tip of the style is called the stigma. Fig. 2. The fruit of the same plant is represented, just before it is ripe. In this, a. points to the fruit-stalk, b. to a division of it, which leaves a single seed, and is called a receptacle, c. is the seed, which is one half of the original germen. ORDER UMBELLIFERE. We begin with this order, since it is the most natural of all orders, and subjects for study are always at hand both in the garden and in the fields. When we say natural, we mean, that the botanist in casting the different genera which compose it into one group or family, has exactly followed the course or dictates of nature; for she has united them by a great many points of affinity and resemblance; whether we contemplate them with the eye of the passing observer, or subject them to the severer scrutiny of a systematic investigation. We shall now explain the general acceptation of the most important terms, and then illustrate their application by reference to the order before us. The cuts we give will help to make our explanation intelligible. Umbel.-When several flowering stalks radiating or proceeding like rays from the same point of the stem, form a surface more or less even. If we understand the term even, as denoting an unbroken superficies, it is applicable whether the surface thus formed be convex, concave, or level; for the surface of a ball and cup may be said to be even, though the former is con vex and the latter concave. Lesser umbel, or umblet: umbellula.When one of the flowering stalks branches into other lesser flowering stalks, which radiate from a common point. In the angelica the lesser umbels are globular. Involucre, involucrum. Leaves that are seated about the point from which the flowering stalks originate, compose the involucrum, and are sometimes called involucral leaves. The reader will remember, that a branch always grows from the bosom or axil of a leaf, which is, in fact, a its parent, so that we may always say we had at hand at the moment of writing of a stem, where is the leaf that gave this. it birth? Hence we might expect to find as many leaves below the centre from which the rays of the umbel diverge as there are rays, but this is seldom the case, these leaves being subject to great variation in number, as well as form. Involucral leaves of the wild carrot, or bird's nest, are branched like a feather. Involucret, involucellum.-The leaves that accompany the lesser or partial umbel. In the fool's parsley, the involucrum is wanting; and the leaves of the involucellum, by hanging down, afford an obvious mark for discriminating this plant. Fruit-bearer, carpophorum.- What is generally called a receptacle among botanists. This term may be applied to whatever immediately supports the fruit. In umbelliferous plants, it generally splits into two slender threads, each of them bearing a seed. In fact, this carpophorum is composed of two others, which if they do not part and show themselves distinct as the fruit ripens, a groove may be seen running up and down in the line of separation. Corolla. That circle which is formed by the coloured leaves of a flower, is termed a corolla, little crown or coronet. In the umbelliferous plants, these leaves are unconnected, and are called petals. These petals are in many genera turned up in a small pointed lappet or tongue, as seen in the bastard stone-parsley. Their number in this order is uniformly five: the stamen rises between, or, in other terms, alternates with the petals, and consists of a filament, or slender thread, which is surmounted by a little head, called an anther, which consists of two cells, that open lengthwise, and discharge the pollen, Calyx, or perianth.-When small leaves, consisting of minute transparent bags, filled by growing from the same point, com- with a yellow fertilizing dust. In this pose a cup for containing the corolla, or in- order the number of stamens in each ternal leaves of a flower, they are called flower is five. The pistil, a small centre stem, the calyx. In reference to the calyx, these is composed of a style or shaft, crowned leaves are termed sepala. They are often by a stigma, which is generally glutinous, joined by their edges, and form a kind of for the detention of the pollen. The tube. Among the umbelliferous plants, base of the pistil is the germen, or rudithe student must look for the calyx in ments or first beginnings of the fruit. In those curious little ridges which in most the umbelliferæ, we have two styles, one to genera are to be found upon the outside of each division of the germen. Stylopodium the seed-vessel. For, by one of those-They are seen to rise through a flat piece countless instances of transformation which of fleshy substance that rests upon the top take place in the constituent parts of a of the germen, which gradually dries up as flower, the divisions of the calyx are the fruit ripens. changed into a covering for the seed. The form and elevation of these ridges, and the nature of the little valleys, (vallecule,) constitute characters, or the establishment of generic distinctions. In the hemlock these ridges are high, and have their edges notched in the cow-parsnip the pair of ridges forming the lips of the seam or suture where the two divisions of the fruit mericarpium, unite, are expanded into a border in the chervil or sheep's parsley, they nearly disappear, and nothing but a smooth surface presents itself. : Vitta.-Under the ridges, or beneath the little valleys, are found small canals which secrete a gum-resin. They are represented in a transverse section of the fool's parsley, which was the only recent plant Seed. The seed presents itself as the twin half of the fruit, disengaged when ripe, and hanging upon the thread-shaped supporter, by its upper end. In this position it is ready to obey the slightest impulse of the air, and only waits for a gust of wind to convey it to a distant spot. By such a simple contrivance has the God of nature provided for diffusing of the seed, and multiplying of each particular species. Albumen.-The substance of the seed is fleshy, or rather horny, when ripe, which, because it furnishes material for the support of the plant in the first stages of germination, or early growth, is called albumen. The albumen in general may be defined to be that peculiar substance within the covering of the seed, which, when under a distinct form, invests the em-, We might represent a peltate, or target bryo, and contains food for its nourishment in the dawn of vegetation. Embryo.-In the upper part of the albumen may be seen, by the help of a magnifier, the minute embryo, having the lower part divided into two lobes, which are called cotyledons. These are nearly equal, and are changed by germination into seed leaves, or that pair which first makes its appearance in vegetation. The upper, or undivided part, is termed radicle, or little root, because in germinating it is lengthened into a root. Fig. 2.-a. Ridge. Fig. 3.-a. Radicle. c. Embryo. b. Cotyledons. a The above cuts of the hemlock represent the parts just described. The leaves of plants belonging to this order, are generally divided and sub-divided into leaflets. They are said to be pinnate, or winged, when ranged in pairs of opposite leaflets along the leaf-stalk; as in the wild parsnip. If these divisions do not reach to the leaf-stalk, or midrib, the leaves are said to be pinnatifid; as in the cowparsnip. If the leaflets are collected together in triplets, the leaves are said to be ternate. În the bupleurum rotundifolium, or thoroughwax, the stem seems to grow through the leaves, which are, in this case, said to be perfoliate. In budding, the leaves are rolled back upon themselves, and seem to burst from their sheath like the unrolling of a spring. The stem is generally hollow and herbaceous. EXAMPLES. Hydrocotyle, umbel simple.-Involucre with three or four leaves; petals without a notch or lappel : seeds nearly round and flattened ridges thread-shaped: without vittae or gum, bearing canals. H. Vulgaris, March penny wort.-This plant may be distinguished by the form of its leaf, which is peltate, or have its expansion roundish, and so placed upon the leafstalk that its surface is nearly horizontal. | shaped leaf, by balancing a penny upon the top of a pencil, though not exactly, for the leaf-stalk is not always in the centre of the expanded part. It is found by the side of streams and ditches. Heracleum.-Fruit elliptical, or oval, flattened, scored by the ridges, which are thread-shaped. Vitte four on the back of the fruit in the little valleys: two in the seam: pair of ridges at each seam, attenuated into a border. H. Sphondylium.- Cow-parsnip: frequent by hedge banks, and is gathered in the spring for rabbits. Conium. - Fruit, nearly globular, with five notched edges on each side. C. Maculatum.-The hemlock may be known by its stem being much branched and spotted. Chaerophyllum.Involucret bent back, concave. Petals with the lappel bent inwards, so as to resemble a heart. Fruit; oblong, smooth. The last is the mark by which the genus may be distinguished. Seed bent inwards. C. Sylvestre. Stem smooth, scored, 'oints rather swoln. Cow-weed Chervil.-Grows in the hedges. for rabbits, sheep's parsley. Called among those who gather it as fodder THE GRATEFUL SOLDIER. L. Under this impression he called the take. man, and told him of the supposed mis he had committed no mistake, that he had The soldier mildly but firmly said, that come with the intention of giving the guinea, that it was the result of the saving of many weeks, and that it was given in pursuance of a resolution which he had made under very particular circumstances. This statement excited still more the attention of the collector; and, at his request, the soldier went, after the service was concluded, to the vestry-room, where he related the following account of himself: : He had been in the early part of his life, educated at a sunday school; where, among other religious instruction which he received, he was taught most of the collects used in the book of common prayer. Some time after leaving school, he entered the army as a private soldier: and here his course of life became so much altered, and he mixed so much with, and adopted the habits of men who had no religious feeling, that he soon lost all that he once possessed. In this way he went on for several years; his early impressions of religion becoming more and more faint, until at last they were nearly worn out. In the progress of his service he was engaged in one of the great battles in which our army had met the enemy, and was most severely wounded; the shock deprived him at first of all sensation; but, when that returned, he found himself stretched on the field, so severely wounded as to be unable to move. The thought of death now came upon him, and brought with it the trembling recollection of the life which he had led, and of his unfitness to appear in the presence of God. He tried to pray; but so long had prayer been neglected, that he could not remember any that he had ever said. At last he brought to mind one of those collects which he had committed to memory when a boy at the sunday school: it was an humble supplication to the Lord for mercy: he repeated it with earnestness and fervour, and found his mind more at ease. Assistance soon after came, and he was removed from the field. He recovered, and, from that hour, became an altered man. In gratitude to God for the mercy which he had found, he resolved to give the first guinea that he could save out of pay, at the first sermon which he should hear preached in aid of sunday schools. T. S. Grimshawe. DIFFERENCE OF TEMPERATURE. A correspondent of the "Times," for October 22, 1834, communicated a copy of his Register of Thermometrical Heights for fourteen days, from which it appeared, that on the 6th of October, the highest temperature was 76°, the lowest 59°; but on the 19th, the highest point to which the thermometer reached was 56°, while 529 was the lowest to which it descended in the night. It is worthy of remark, that while the heat in the shade, by day, had declined 20°, that in the night had fallen only 7°. The cause of this was the alteration from a clear to a clouded atmosphere, added to what is due to the sun's change in declination, or noontide altitude. Now, a denser atmosphere in the day-time diminishes the heat of the sun experienced at the earth's surface, by hindering the appulse, or access, of all the rays which are sent towards us; a clouded sky, at night, stops the radiating, or passing off, of the heat, by interposing a barrier of vapour in a state of condensation, between the earth and the surrounding space. The same condition of the air which operated in depressing the highest temperature registered by day, had the effect of checking that depression at night. We therefore find the same cause, an increase in the density of the vapour, producing opposite effects under different circumstances, and yet with one precise object, namely, that of circumscribing the extent of the thermometrical range. We see how order is provided for and secured in the midst of apparent disorder; how in the midst of inclemencies of change, a tender regard is manifested for animal and vegetable natures. The more severe and rigorous the scrutiny is to which we subject the operations of creative intelligence, with a fuller soul and greater comprehensiveness of meaning do we say, "He hath done all things well." And when we make ourselves acquainted with the laws which direct and control all those changes that the course of nature exhibits, we see in the methods by which they are brought about, that God, in his workmanship, doth often hang the greatest weights upon the smallest wires. In the arts and manufactures, we always see the greatest effects produced by the simplest causes; and were we, in our daily callings, and in the ever-recurring turns of social duty, always to make a singleness of means the ruling principle of our plans and endeavours, we should be more serviceable to our friends, and more comfortable with ourselves, and altogether sustain, with a better grace and propriety, the character of good citizens and consistent christians. SOCIETY. IN the island of Teneriffe, the writer, for the first time in his experience, met with a community among spiders. The species alluded to were of the diadem kind; the web common to several individuals was multifarious and extensive, interspersed with small canopies of exquisite texture, under each of which a spider was seen watching. By what arrangement animals so fierce and unsocia |