THIS is one of those interesting families which are brought within the range of our domestic acquaintance by the relation that some of their component members bear to the purposes of life in serving as articles of diet or medicine. That well-known and useful vegetable, the potato, is the root, (tuber,) or rather the subterranean stem of the solanum tuberosum, which may properly stand as the head and representative of all its brethren. The calyx is divided into five segments, and often permanent, that is, continues to accompany the fruit after the other parts of the flower have fallen off. The corolla is also cleft into five divisions, and bears as many stamens from its base. The fruit is divided into two cells by a partition which is bisected on each side by a ridge crowned with the seeds. This position of the seeds may be rendered easy to the apprehension by cutting one of the green capsicums or chilis across, and observing how the seeds descend in the middle line on each side of the partition. If the reader should happen to take a pleasure in investigations of this kind, he may remove the covering of the seed itself, when he will perceive, by the help of a little patience, that the embryo, something like a small pale worm, is curled round a white substance which is called the albumen. The characters we have now given are the leading ones, as far as the fructification in its parts are concerned; but the appearance of this family was long ago considered as pecuiarly indicative of the dangerous qualities which many of them possess: as if the providential care of God had given us a cautionary notice and warning in the gloomy aspect and unlovely hues and scents of certain plants, that we may not proceed at once to taste the fruit, which is often attractive, or apply their foliage to purposes of diet, till trial and experiment can vouch for the safety of their use. To remind the reader of their poi sonous character, we need mention only the atropa belladonna, or deadly nightshade, and the hyosicamus niger, or henbane. It will, therefore, at first sight appear a little singular that the potato should belong to a family impressed with qualities so much to be dreaded; but to explain the discrepancy by reference to analogy, we have only to recollect what a curious change the process of earthing up effects in a stem, as in the celery and sea-kale, for example. Take a stem of the former, when ripe, and bite off a piece that has grown two inches below the earth's surface, and then a piece that has grown two inches above the earth's surface, and then mark what a difference in flavour and quality. The potato is a free stem propagated by the parent, and is ripened for use by lying in the soil precisely as in the two instances just cited. When a potato is exposed it turns green, as a stem in natural course does, and, as an eatable, becomes unwholesome and disagreeable. After having stated thus much in reference to the potato, which, as we may hint by the way, came originally from Mexico, we may go on to mention a few examples for further illustration and exercise. The datura stramonium, or thorn-apple, which is a native of this country, but frequently finds a place in our gardens. The thorny points upon the seed-vessel render it a plant of easy recognition, though these are not essential to the genus datura, but the fourvalved capsule and funnel-shaped plaited corolla. The gloomy appearance and disagreeable smell may easily suggest a recollection of the general character of the solanaceæ. The bitter-sweet and the black nightshade are easily known by the exact resemblance which their flowers have to those of the potato. The former (solanum dulcamara) produces berries of a bright red in our hedges, while the latter (solanum nigrum) yields black ones upon compost and among rubbish. Hence we may The tea plant, (lycium barbatum,) which forms such a fast-growing covering for bowers and walls, belongs to this family. It is a native of France and Japan, where it is used sometimes as a substitute for tea: whence its name. infer that though its blossom has a melancholy hue, it possesses but little of those narcotic properties which are found in many others of the same order. We may also refer to other examples in the mulleins, which it would seem are neither hurtful nor unsightly. This genus (verbascum) distinguished by its wheel-shaped corolla and its bearded filaments, comprehends several species which are occasionally seen in gardens, and are remarkable for a long spike of yellow flowers, and the downy covering of their leaves. The great broad-leaved mullein (verbascum thapsus) is often a solitary but a conspicuous object by road sides. Its tall, straight stem, bright yellow flowers, and pale downy leaves will always point it out as the plant in question. The winter cherry, (physalis alkekengi,) so remarkable for the enlargement of the calyx, claims a space here; the blossom very much resembles that of the potato, while the pulpy seed-vessels, when ripe, make an agreeable dessert, especially in hot climates. This example shows that the gloomy appearance, joined to the botanical characteristics, may be esteemed a salutary caution, and is not an invariable prohibition against eating the fruit of these plants. The last we shall name is the nicotiana tabacum, or tobacco plant. The narcotic properties of this pernicious weed are soon felt on the first trial of the inexperienced, while they are subsequently attested by the haggard looks and declining appetite of those who yield themselves to its indulgence. THE TELESCOPE.-No. III. as it represents objects under an angle greater than is presented to the naked eye. (See the cut representing the different angles under which the man is viewed, in the 2nd column of page 372) The moon, for example, appears to the naked eye under an angle of half a degree; consequently, a telescope magnifies one hundred times, when it represents the moon under an angle of fifty degrees, which is one hundred times greater than half a degree. If it magnified two hundred times, it would represent the moon under an angle of one hundred degrees: and the moon would, in that case, appear larger than one-half of the visible heavens, whose whole extent is only one hundred and eighty degrees. It therefore happens, that, in viewing the moon through a telescope of a high magnifying power, a small portion only of her disk is visible at a time; because the size of the telescope remains the same, whilst the apparent size of the moon is increased consequently, the telescope must be moved about, to view different parts in succession, in order to examine the whole. Thus a telescope whose object lens (that is, the glass next the object, or at the further end of the telescope) is three inches diameter, when it is adapted to magnify about forty times, it will show the whole surface of the moon at once, as shown in figure No. 1; if a power of one hundred be applied to the same telescope, it will show a much less portion of the moon at a time, but greatly mag A TELESCOPE magnifies as many times nified, as represented in figure, No. 2. mind the reader of the following general | a point, then it is clear that a concave particulars, which we have before explained; namely, by a convex lens parallel rays are rendered convergent, and convergent rays parallel; thus, a a (a, a, parallel rays; b, b, convergent rays.) and convergent rays become still more so, and the reverse as before; thus, a α a b b a A B is a convex lens, called the objectglass of the telescope, whose focus is at the point E, which (as explained at page 372) is the point where the image of an infinitely distant object would be formed by the parallel rays which fall upon the glass being refracted in passing through it, so as to converge to this point. C D is a concave lens, called the eye-glass, which is placed nearer to the object-glass than the point E, by the distance of its own focus, so that the point E is the focus of both glasses. Now, the parallel rays, after passing through the object-glass, converge towards the focus E; but it is evident, that before they arrive at that point, they must pass through the eye-glass C D, which, being concave, cause all converging rays to become parallel, as before stated; therefore, the rays on leaving the eye-glass, again become parallel to each other, as they were when they first reached the object-glass. By thus rendering the ravs | c, d, parallel.) parallel, to enter the eye of a person placed at E, more distinct vision will be obtained, as objects are, in all cases, best distinguished when they are so distant that the rays of light from them which fall on the eye are parallel to each other. The magnifying power of such a telescope as above described, amounts to as many times as the focal distance of the object-glass A B is greater in length than that of the eye-glass c D. Thus, supposing the distance of the objectglass A B, from its focus E, to be thirtysix inches, and that the distance of the eye-glass c D from its focus (which is the same point E) is one inch; then the difference between these two focal distances is thirty-five inches, and therefore such a telescope would magnify thirty-five times, or the object viewed would appear under an angle thirty-five times greater than when viewed by the naked eye. It hardly need be remarked. that the glasses are fixed in a tube, though not so represented in our figure. When a telescope is directed towards the heavens, or to very distant objects on the earth, the space discovered appears in the figure of a circle, that being the aperture of the tube which forms the telescope; and we see those objects only which are included in that space; so that to examine other objects, the position of the instrument must be altered: this circular space presented to the eye of the spectator is called the field of the telescope. It will readily be understood, that it is a great advantage to have a very large field of view; for suppose two telescopes directed to the moon, by the one of which we can discover only a portion of that luminary, whereas by the other we see her whole body, together with the neighbouring stars, (see our cut, Fig. 1, and Fig. 2,) the field of the first is, therefore, much greater than that of the other: and relieves the observer not only from the trouble of frequently changing the position of the instrument, but procures another very great advantage, that of enabling us to compare several parts of the object, one with another, by viewing them at the same time. The extent of the apparent field of a telescope will, however, depend upon the magnifying power employed. A much lower power, as before explained, will enable us to discover the whole illuminated surface of the moon at once; but an increase of power produces a correspondent diminution of the apparent field, because, while we increase the apparent size of the object, the diameter of the telescope remains the same. It is consequently desirable, that a telescope should have as large an aperture as possible, by which means a higher magnifying power may be advantageously employed. OLD HUMPHREY'S ADDRESS TO A NEWMARRIED COUPLE. I HAVE a message for you, a high and a holy message, coming from a high and a holy source; one that concerns your comfort, your enjoyment, and your peace. An attention to it will shield you from many sorrows; a neglect of it will burden you with many calamities. Now mind that you receive it in a friendly, kind-hearted way. The Psalmist cried out, "Behold, how good and how pleasant it is for brethren to dwell together in unity!" And if it be goodly and pleasant for brethren to do this, surely it must be still more so for husbands and wives. Receive, then, the mes sage with affection, " Bear ye one another's burdens." Did you ever find your hearts fill with joy when you beheld a married couple surrounded with comforts, animated with the same hope, journeying on together towards the same heaven, affectionately loving and highly honouring each other; and, in addition to all this, bearing each other's burdens? Oh it is a lovely, a glorious thing in this world of affliction, to find hearts knit together in sorrow and in joy, sharing with equal willingness the shine and the shade! And have you never looked with pain upon an ill-matched pair, reminding you of dogs chained together, pulling different ways? Have you seen the eye inflamed with wrath, whilst the tongue was venomed with bitterness, and discomfort, clamour, and confusion reigned around? Oh it is a bitter and an evil thing for those who are in wedded life to dwell in hatred, not in love; increasing, instead of bearing each other's burdens. I know not how it may have been with you, but the experience of Old Humphrey has taught him that troubles will come without being sought after, and that there are thorns and briers enough in the world, without our gathering them and planting them in each other's bosoms. You have just entered on a new life, and God of his mercy grant that it may be a happy one; but as it was of olden time, so it is now, weeds spring up in the fairest gardens. Such is the evil of our nature that the cockle will grow with the wheat, and the thistle with the barley; and so long as the human heart is not wholly sanctified with God's grace, so long will its infirmities ever and anon get the upper hand, setting at variance those whose heart-strings should be twined together; bear, then, with a few remarks from Old Humphrey. Perhaps you have known each other from the days of youth, and succeeding years may have strengthened your affection. You were, perhaps, so well acquainted with each other's dispositions and qualities, that marriage has not made manifest a single infirmity that you did not know before. If so, happy are ye. But if, on the contrary, when you entered into wedded life, you were but half acquainted with each other; if circumstances were not favourable to that thorough knowledge which beings eating of the same bread, and drinking of the same cup, and sharing the sweets and bitters that fall to the lot of humanity, ought to possess, why, then, make amends for this disadvantage as far as you can, by bearing each other's bur- | silver make to themselves wings and fly dens. It is an easy thing to love what is lovely in each other, to smile when the sun shines, and to be kind and good-tempered when your partner is kind and good-tempered too; but this is no proof of real affection. away. What if want should take the place of plenty? Will you then look kindly on each other? Will you then bear each other's burdens? You are in health, but you cannot reasonably expect to remain so long; the tooth-ache, the head-ache, the heart-ache, and a hundred other ails are known by others, and are likely enough to be felt by you, and they may try you sorely; and if care, want, and sickness, should meet to need of all your affection, ay, and of God's grace, to enable you to remain kindly affectionate one to another, and to bear one another's burdens. Can you put up with each other's infirmities, bear with each other's waywardness, and forgive each other's errors? This is proving your affection; this is, indeed, bearing one another's burdens. Old Humphrey is in the habit of putting some search-gether in your habitation, you will have ing questions; questions that at times go right to his own heart, while he means them to go to the hearts of others; he feels his infirmities, and smarts under his own correction; so much, as to be half disposed to blot out the observations he has made; but he will be faithful in spite of his infirmities; he will speak plain truths, ask plain questions, and make plain remarks, whoever may be affected by them. It is a clear case, that "two cannot walk together unless they are agreed;" but if they are agreed, they get on wonderfully well. The one may be stronger or weaker, bolder or more timid than the other, but that will not signify. The one may be a good walker, and the other a very bad one; there may be some lameness or weakness in the one, and not in the other; but still they will so accommodate themselves to each other's infirmities, that they will go forward in comfort and peace; and if this be true of any people in the world, it is particularly so of married people. The path may be stony, the hill may be steep, the hedge thick and thorny, the stream strong and deep; but all will be overcome by helping each other along, by encouraging each other, and by bearing each other's burdens. I trust that you have not built your hope of earthly happiness on the mere attractions of each other's persons. A handsome face and an agreeable way of behaviour are but a poor stock of comforts to begin housekeeping with. You have something better than these, but have a care how you begin; for a good beginning is the best preparation for a good ending. You are now at ease; but as the fairest summer has its thunder-cloud, so surely will the smoothest life have its cares. Are you ready to meet with disappointment and anxiety? Are you ready to bear each other's burdens? Your wants appear to be well supplied. In Scripture language your heads appear anointed with oil, and your cup runs over; but it may not always be so, for gold and If you cannot travel together with affection, you will find hatred and unkindness but sorry companions. If helping each other will not do, hindering one another will do worse. If bearing one another's burdens will not enable you to trudge along tolerably comfortable, you will make but a sad business of it, by adding to each other's load. Therefore "Bear ye one another's burdens." If you have made your calculation for fine weather only, go and bespeak an umbrella, for be sure you will have need of it. If you think to look at each other always with the same fond and affectionate regard that you have yet done, Old Humphrey tells you, in spite of your fairy dreams of unabated love, that if you go through the first year of your married life without a single heart-burning, you will deserve to have your pictures framed and glazed, and hung up in the market-hall for universal admiration. No! no! Old Humphrey will tell you the truth; however you try to flatter and deceive one another, you are a pair of poor, weak, erring, sinful creatures, requiring Divine aid every moment of your lives, to keep you from inattention, from wanderings of heart, from selfishness, from bitterness, and from hatred. If you really wish to love one another always, you must love God always for none but God can preserve your affection, and enable you to bear each other's burdens. And, mark me, when the time comes, as come it will, when you feel yourselves to be overtaken in a fault, when you have been angry one with another, be faithful in questioning your own hearts. Say to yourselves in private, "Am I sure the fault is not mine? Have I not been thoughtless, unreasonable, selfish, hasty, or bitter? If in the wrong, have I made acknowledgment of it, and am I anxious to avoid my error |