formed, which present a very neat appearance. By spreading the liquid on the sur face of nankeen, Dr. Howison formed a cloth, which was very flexible, and perfectly impervious to water. He recommends this cloth as a suitable material for garments; no sewing would be required; the edges of the different pieces being placed in contact, and wetted with the recent juice, would adhere, and the article would be ready for use. From these facts, it is obvious, that if caoutchouc could be procured in large quantities in a fluid state, it might be applied to many important purposes. It, therefore, becomes an object to devise some means by which the solid gum, as it is found in commerce, could be wrought into the different forms best adapted to various uses. From a variety of experiments made by different individuals, the following results have been obtained : When heated in close vessels, to a high temperature, caoutchouc melts into a black viscid substance resembling tar, which does not concrete on cooling. When this substance is incorporated with oil of turpentine it forms a tough varnish, which may be removed by means of a brush, charged with warm oil of turpentine. Mode of making gum elastic into bags, sheets, &c.-Soak the gum elastic in sulphuric ether, until it becomes soft and almost inelastic, which, in good ether, will take from ten to twenty-four hours. Then, if it is a plate, cut it with a wet knife, or parallel knives, into such sections, sheets, or shapes, as may be desired; and suffer them to dry. Or, if a bag, or a bottle, apply a pipe, or a stop-cock to the neck, and inflate it with the mouth; rapidly, if the bag should expand equally; more slowly, and with occasional pauses, if unequally. By such means a bag may be made so thin as to become transparent, and light enough to ascend, when filled with hydrogen gas. By graduating the extent of inflation, sheet caoutchouc of any given thickness is produced. If for blow-pipes, or other purposes, for which it is desirable that the bags should possess contractibility, let them be inflated to the desired size; and, after an hour, let out the air. Ever afterwards they will suffer as great a degree of extension, and again contract. If permanent sheets are wanted, the inflated bags are to be hung up until dry, after which no sensible contraction will ensue. Bags softened by ether may be readily stretched by hand, over lasts, hat-blocks, or other moulds, so as to assume the shapes desired; and may, therefore, be applied to a variety of useful purposes. In the form of straps, and twisted strings, its elasticity offers many useful applications. It may be made to assume the form of a tube, to connect parts of chemical and other philosophical apparatuses with each other; it may be employed as covers for bottles, stopples, &c.; and, indeed, wherever the passage of steam, or air, is to be prevented. It is also susceptible of numerous applications in medicine and surgery. Dr. Mitchell has extended a bag, or bottle, of caoutchouc, which was about the size of an English walnut, and which weighed three drachms and a half, until its diameters were enlarged to fifteen, and thirteen and a half inches respectively. Larger bottles have been made to attain a diameter of six feet; one of these, when filled with hydrogen gas, escaped, and was found at the distance of one hundred and thirty miles from the city! Balloons, so formed, have been exhibited before the different classes attending chemical lectures in Philadelphia. The discovery, by the same gentleman, that the essential oil of sassafras will soften caoutchouc, so that it may be applied upon any surface with a brush, promises, also, much utility. When dry, it becomes again simple caoutchouc, with all its original elasticity. If it be applied on a plate of glass, dried, and then immersed in cold water, the sheet may be peeled off. It has been spread upon paper, and, after becoming dry, the whole was immersed in water; when on stretching it, the paper would, of course, separate into fragments; between which, the gum elastic might bé stretched so as to separate them to the distance of a quarter of an inch, without itself giving way, notwithstanding its tenuity. Such a varnish will never crack, one of its essential attributes being elasticity. Boiling water softens caoutchouc, but does not dissolve it; two pieces, which have been boiled for a long time, when strongly pressed together, form a permanent adhesion with each other. When softened in this manner, it may be drawn out into thin lamina, resembling gold-beater's skin. An artist, Mr. Matthias More, conceived the idea of substituting transparent slips of caoutchouc for the glass slides on which the figures are painted, for magic lanterns. He purposed to paint, or print, the figures on a long slip of caoutchouc; this was to be wound on and off a cylinder, thus bringing the figures successively before the lens. By soaking the caoutchouc for many hours in warm water, he succeeded in stretching it to a very great extent, and in rendering it very thin and transparent. Bottles of this substances were inflated by means of a pair of bellows-the bags thus formed, when filled with hydrogen gas, ascended into the at mosphere. Gum elastic bags may he dilated, without previously softening them, by forcing in air with a condensing-pump. When caoutchouc is boiled in the expressed vegetable oils, in wax, butter, or animal oil, it is dissolved; and, combining with these substances, forms viscid inelastic compounds. Ether, naphtha, and cajepur oil, appear to be the only solvents from which it can be separated unchanged. When the ethereal solution is poured upon water, it spreads equally over the surface, the ether rapidly evaporates, leaving a thin film of caoutchouc, which retains all its characteristic properties. The rapidity with which the ether evaporates, renders it very difficult to apply this solution to any practical uses; this, together with the expensiveness of the solvent, has hitherto rendered its applications extremely limited. "In order to form tubes of caoutchouc, the best method is to cut a bottle of this substance into a long slip (spirally), and soak it for half an hour or an hour in ether; by this means it will become soft and tenacious, and if wound dexterously on a greased mould, bringing the edges into contact with each other, at every turn, and giving the whole a moderate and equal pressure, by binding it with a tape wound in the same direction as the caoutchouc, a very effectual union will be produced. Dr. Roxburg, to whom we are indebted for a botanical description of the East Indian vine, from which the caoutchouc is obtained, dis solved this substance in cajeput oil. When alcohol is added to this solution, the caoutchouc is separated from the oil, and floats upon the surface, in a semi-fluid state; when exposed to the air it becomes firm, and retains its elasticity perfectly. "Mr. T. Hancock has succeeded by a process, which he has not published, in working caoutchouc with great facility and readiness. It is made into large cakes, and being cut with a wet knife into leaves or sheets, about one-eighth or one-tenth of an inch in thickness, can then be applied to almost any purpose for which the properties of the material renders it fit. The caoutchouc thus prepared is more flexible and adhesive than that which is found in the shops, and is worked with singular facility. Recent sections, made with a sharp knife or scissars, when brought together and pressed, adhere so firmly, as to resist rupture as strongly as at any other part; so that if two sheets be laid together, and cut round, the mere act of cutting joins the edges together; and a little pressure on them makes a perfect bag of one piece of substance. The adhesion, in those parts where it is not required, is entirely prevented by rubbing them with a little flour. Bags made of this substance have been expanded by having air forced into them, until the caoutchouc was quite transparent; and when expanded by hydrogen gas, they were so light, as to form balloons with consider able ascending power; but the hydrogen gas gradually escaped, perhaps through the pores of this thin film of caoutchouc," Dr. John K. Mitchell bas lately formed large balloons of caoutchouc by softening the bottles in ether, and afterwards inflating them; it was one of these balloons, filled with hydrogen gas, which rose into the air, and fell, as above-mentioned, at the distance of one hundred and thirty miles from the place of its ascension. The elasticity and tenacity of caoutchouc, its power of resisting the action of most chemical agents, and the recent improvements in working it, promise to render its applications in the arts much more extensive than they have hitherto been. The process for softening the caoutchouc, is, by leaving the bottle for ten or twelve hours in common ether; and then to blow it out to the desired thinness, by fastening into the neck a tube, with a stop-cock. FACTS ON WHICH THE "BRIDE OF LAMMERMOOR" WAS FOUNDED.+ Miss JANET DALRYMPLE, daughter of the first Lord Stair, and Dame Margaret Ross, had engaged herself without the knowledge of her parents to the Lord Rutherford, who was not acceptable to them either on account of his political principles, or his want of fortune. The young couple broke a piece of gold together, and pledged their troth in the most solemn manner; and it is said the young lady imprecated dreadful evils on herself should she break her plighted faith. Shortly after a suitor who was favoured by Lord Stair, and still more so by his lady, paid his addresses to Miss Dalrymple. The young lady refused the proposal, and, being pressed on the subject, confessed her secret engagement. Lady Stair, a woman accustomed to universal submission (for even her husband did not dare to contradict her), treated this objection as a trifle, and insisted upon her daughter yielding ber consent to marry the new suitor, David Dunbar, son and heir to David Dunbar, of Baldoon, in Wigtonshire. The first lover, a man of very high spirit, then interfered by letter, and insisted on the right he had acquired by his troth plighted with the young lady. Lady Stair sent him for answer, that her daughter, sensible of her undutiful behaviour in enter ing into a contract unsanctioned by her parents, had retracted her unlawful vow, and now refused to fulfil her engagement with him. The lover, in return, declined possitively to receive such an answer from any one but his mistress in person; and as she had to deal with a man who was both of a most determined character, and of too high condition to be trifled with, Lady Stair was + From Notes to the New Edition of the Waverley Novels. 1830. obliged to consent to an interview between Lord Rutherford and her daughter. But she took care to be present in person, and argued the point with the disappointed and incensed lover with pertinacity equal to his own. She particularly insisted on the Levitical law, which declares that a woman shall be free of a vow which her parents dissent from. This is the passage of Scripture she founded on : * " If a man vow a vow unto the Lord, or swear an oath to bind his soul with a bond, he shall not break his word; he shall do according to all that proceedeth out of his mouth. "If a woman also vow a vow unto the Lord, and bind herself by a bond, being in her father's house in her youth; "And her father hear her vow, and her bond wherewith she hath bound her soul, and her father shall hold his peace at her: then all her vows shall stand, and every bond wherewith she hath bound her soul shall stand. "But if her father disallow her in the day that he heareth; not any of her vows, or of her bonds wherewith she bath bound her soul, shall stand; and the Lord shall forgive her, because her father disallowed her." Numbers xxx. 25. While the mother insisted on these topics, the lover in vain conjured the daughter to declare her own opinion and feelings. She remained totally overwhelmed, as it seemed mute, pale, and motionless as a statue. Only at her mother's command, sternly uttered, she summoned strength enough to restore to her plighted suitor the piece of broken gold, which was the emblent of her troth. On this he burst forth into a tremendous passion, took leave of the mother with maledictions, and as he left the apartment, turned back to say to his weak, if not fickle mistress, "For you, madam, you will be a world's wonder;" a phrase by which some remarkable degree of calamity is usually implied. He went abroad, and returned not again. If the last Lord Rutherford was the unfortunate party, he must have been the third who bore that title, and who died in 1685. The marriage betwixt Janet Dalrymple and David Dunbar, of Baldoon, now went forward, the bride showing no repugnance, but being absolutely passive in every thing her mother commanded or advised. On the day of the marriage, which, as was then usual, was celebrated by a great assemblage of friends and relations, she was the samesad, silent, and resigned, as it seemed, to her destiny. A lady, very nearly connected with the family, told the author that she had conversed on the subject with one of the brothers of the bride, a mere lad at the time, who had ridden before his sister to church. He said her hand, which lay on his as she held her arm round his waist, was as cold and damp as marble. But, full of his new dress, and the part he acted in the procession, the circumstance, which he long afterwards remembered with bitter sorrow and compunction, made no impression on him at the time. The bridle feast was followed by dancing; the bride and bridegroom retired as usual, when of a sudden the most wild and piercing cries were heard from the nuptial-chamber. It was then the custom, to prevent any coarse pleasantry which old times, perhaps, admitted, that the key of the nuptual-chamber should be intrusted to the brideman. He was called upon, but refused at first to give it up, till the shrieks became so hideous that he was compelled to hasten with others to learn the cause. On opening the door, they found the bridegroom lying across the threshold, dreadfully wounded, and streaming with blood. The bride was then sought for; she was found in the corner of the large chimney, having no covering save her shift, and that dabbled in gore. There she sat grinning at them, mopping and mowing, as I heard the expression used; in a word, absolutely insane. The only words she spoke were, "Tak up your bonny bridegroom." She survived this horrible scene little more than a fortnight, having been married on the 24th of August, and dying on the 12th of September, 1669. The unfortunate Baldoon recovered from his wounds, but sternly prohibited all inquiries respecting the manner in which he had received them. If a lady, he said, asked him any question upon the subject, he would neither answer her, nor speak to her again while he lived; if a gentleman, he would consider it as a mortal affront, and demand satisfaction as having received such. He did not very long survive the dreadful catastrophe, having met with a fatal injury by a fall from his horse, as he rode between Leith and Holyrood House, of which he died the next day, 28th of March, 1682. Thus a few years removed all the principal actors in this frightful tragedy. FANCY'S DREAM. I SOMETIMES fancy, as I gaze upon 1 WHY? AND BECAUSE."+ Why does the mercury sink when the weather is damp? Because steam is lighter than pure air, and introducing itself into the column of air, the weight of which kept the mercury suspended, this liquid now pressed in a less degree, sinks a few lines. Why during excessive heats, and especially in stormy weather, do we feel ourselves oppressed, weary, and uncomfortable? Because the air being rarified by the heat, or charged by humidity, no longer presses upon us with sufficient force to keep in equilibrio the air that is within our body; and this interior air expanding, occasions the inconvenience that we feel in this circum stance. Why if two hollow hemispheres, or caps, be applied one to another and hermetically sealed, the interior air being drawn out by an air-pump, are the two parts so strongly fastened to each other, that a man's utmost strength would not be able to separate them? Because the exterior air presses with all its weight on the hemispheres, there being no interior air to counterbalance it; consequently, supposing each hemisphere to be six inches in width, or diameter (a column of atmosphere causing a pressure of nearly ten pounds on a circular space of an inch diameter), the force necessary to separate the two caps, must equal a weight of four hundred pounds. Why do chesnuts crack with a loud noise when one has not the precaution to split them before they are laid on the hot ashes? Because the air confined under the shell expanding by the heat, acts with so much the more force to make itself a passage, as it meets with greater resistance; when therefore the shell is thick, it bursts with greater violence. The same effect does not take place when the chesnut is split, because the air within it expands, finds a passage through which it freely escapes. Why do chimneys smoke? Because the room doors are closed, or the chimney flue being very long, the inferior air is with difficulty renewed, in order to replace that which the action of the fire rarefies; this rarefied air therefore flies with the smoke into the apartment where it finds less resistance than in the flue; but this inconvenience ceases when a door is half opened, the exterior air then having a free passage, repels that of the room, and constrains the smoke to go up the chimney. + From Why and Because, being a collection of familiar Questions and Answers, on subjects relating to Air, Water, Light, and Fire. London, 1830. Why do fishes die when the pond is covered with a coat of ice? Because the air necessary for their respiration, and consequently for their existence, can no longer reach them. It is therefore necessary to make in different places openings to admit air. Why should not apparently drowned persons be suspended with their heads downwards? Because it is not so much the water that has entered their bodies, that has rendered hem torpid, as the want of circulation of air; if therefore they are placed with their heads downward, they are in danger of being suffocated by producing a super abundance of blood towards the brain. In order to restore such persons to life, endeavours must be made to renew the circulation of blood by moderate warmth, by friction, by the use of spirituous liquors; air must be injected into their nostrils and lungs, and above all, they must be kept in their natural position. Why in a cellar filled with wine in a state of fermentation, cannot a candle remain a-light? Because the exhalations arising from the wine and supplying the place of the atmospheric air, are of a nature neither to supply fuel to fire, nor even to support life; for if a man were to place his nostrils to the bung of a pipe of wine in a state of fermentation, and inhale the exhalations, he would drop down dead, as if struck with a thunderbolt. Many instances of this have oc curred. Why does fire burn more ardently in excessively cold weather? Because the air being more dense, affords more nourishment to the fire. Why is fire in a chimney immediately put out, by carefully blocking up both passages? Because, to keep up a fire, not only must the inflamed materials be surrounded with air, but the air must have a free passage and possess a certain pureness. But when the chimney flue is hermetically closed, the air inside is no longer free, it cannot be re newed, and as soon as the combustible parts. of the inclosed air are consumed, the fire is extinguished. Why does water in a vessel placed on thes fire simmer before it boils? Because water, like all other materials, contains air, the gross parts of which expanding by the heat, increase the body of the water, and remove with violence whatever opposes their extension and ascension.. Why are fogs caused? Because the vapours and exhalations arising from the earth, condensed by the cold, and too heavy to support themselves in the elevated regions of the atmosphere, remain i in the inferior regions, where they change the transparency of the air, and partly fall again in very fine rain. Why do the panes of glass in our apartments get covered inside with rime frost in winter time? Because the interior air, which is warm and charged with vapours, is attracted towards the glass, and then losing its heat, it abandons at the same time the humidity which it possessed; these vapours are condensed, fasten on the panes of glass, and if the exterior cold be sufficiently intense, are converted into ice. Why do clouds produce rain? Because the particles of water of which they are composed, adhering to each other, form drops too heavy for the air to sustain them; they then fall on the earth through their own weight. Why do some persons talk of showers of blood, sulphur, fire, &c.? Because the ignorant and vulgar, without examination, call any thing but what is in reality, blood or sulphur. The learned, however, have proved that these colours proceed from certain particles of dust which the wind sometimes transports to great distances. As to showers of fire, they are more founded on fact, but there are few instances of them. Why does hail fall in summer time ? Because the vapours being extremely rarified by the heat, ascend to a very elevated region, where the cold seizes them, and converts them first into drops of water, and then into hailstones. Why do we hear the same sound only once, though we have two ears ? Because the sound strikes certain points which have a point of re-union in the brain. We experience, therefore, only one impression, but that impression is twice as strong as it would be, had we only one ear. Why does not the wind always blow with the same force? Because wind arises from a collision in the mass of air, and this collision is subject to different causes. First, the expansion and sudden condensation of the air by the influence of the sun, or the absence of heat. Second, the motion of the earth, which turns daily on its own axis, from west to east, &c. When, therefore, these different causes re-unite, the agitation of the air is necessarily more violent. Allowances must also be made for obstacles that the wind finds in its course; mountains, forests, clouds, and edifices, contribute to the va riation it experiences. Why, in our climates, are east winds generally dry ? Because they traverse, many lands, few seas, and consequently can imbibe but few humid vapours. VOL. IV. 3 B Why is the south wind hot and foreboding of rain ? Because this wind, which comes from Africa, or countries where the heat is continual, drives before it warm vapours; it then passes over the Mediterranean Sea and English Channel, where it imbibes humid vapours, which are converted into rain when acted upon by the cold of our climates. Why is the north wind cold, and often rainy? Because this wind comes to us from the northern regions, where are mountains of perpetual snow, which spread an excessive cold. This wind, moreover, crosses several seas, the vapours of which form clouds, which it carries along with it. Why does not a west wind, which traverses the ocean, always bring on rain ? Because the wind, though coming from the west, or from any other point where it may imbibe vapours, sometimes blows in a direction that it disperses and scatters those vapours before they have reached a sufficiently elevated region of the atmosphere, to be able to be condensed and reduced into drops of rain. Why, when wine is mixed with water, and in this mixture a piece of list soaked in wine is plunged, and the other end placed in an empty vessel, does the wine separate itself from the water? Because the wine has more affinity, that is, unites better with wine than with water; it is, therefore, attracted towards the vinous particles of the list, which finding itself too full, distils in the empty vessel its superabundance of liquid. Why, if a body be weighed in water, do we find that it has not the same weight as when weighed out of the water? Because the liquid which it displaces, supports it, and frees it from the weight of its own bulk. Thus, if the mass of water displaced be of two pounds, the body will weigh two pounds less, when in the water than when out of it. Why do the strings of a strung guitar break when the weather is damp ? Because the dampness, or the water reduced into vapour, penetrates bodies, extends them, and thus increases their bulk. For instance, paper, parchment, all woods (especially deal), and animal membranes, aré lengthened and increased when humidity affects them. Cords, on the contrary, being composed of stout and slight filaments, swell and thicken. Thus the strings of a piano, strung tightly, break as soon as the humidity, by penetrating them, increases the tension. Why do the little capuchins, sometimes made for us to indicate the state of the atmosphere, cover themselves with their cowl when the weather becomes fine ? Because the cowl is put into motion by |