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accomplishment of the object nnder consideration, we will endea- blowpipe, that is, by the introduction of a jet of oxygen inb vour to make plain,
the flame of pure hydrogen. Submitted to this heat, the hardest We will suppose the lower piece of charcoal, in an upright metals not only melt like wax, but are boiled and converted electric lamp, to be fixed at one end of a balance-lever or beam, into vapour. Even the diamond itself cannot remain in the to the other end of which is attached a piece of iron somewhat presence, but is burnt up and transformed into gaseous matte. heavier than the charcoal, this piece of iron being placed within There are, however, some substances, which, with the greatest a coil formed by a portion of the conducting wire of the battery. heat at present attainable, will not burn, and one of thesa The weight of the iron will in this case determine the prepon- is lime. The action of the oxyhydrogen blowpipe on lim, derance of the balance-beam in its favour, when no current is therefore, can only render. it incandescent, or white hot, but so passing, and will thus cause the two charcoal points, their posi- intensely and luminously hot that no eye can gaze on it for : tion being so arranged beforehand, to be in contact with each moment without injury, Neither the discovery nor the use of this other. If the circuit be now comploted, the electric current will light are modern. It has been successfully used for illuminating flow through the charcoal points, and the spark of light will dissolving views, both at the London Polytechnic Institution and appear, but at the same instant the current flowing through the elsewhere, for very many years. It was first used in 1826 b; coil will draw the piece of iron upwards, and the charcoal points Lieutenant Drummond, who then had the conduct of the Ordwill consequently be drawn apart, the electricity, in the form nance Survey of Scotland and Ireland, and who employed it for of the art of light before referred to, continuing to flow between signals in connexion with that survey. By collecting its rays in them. If the adjustments be made with delicacy, the distance to the focus of a paraboloid he was able to render it visible all the which the iron will be attracted upwards will be exactly equal to way across St. George's Channel, from a point near Holyhead that to which the charcoal points should be drawn asunder; into Ireland, a distance of sixty-four miles, and subsequently, in and should an accidental circumstance (such as the fracture of the Scotland, from the summit of Ben Lomond to that of Knock charcoal points in consequence of the heat) occur to break the Layd, a distance of ninety-five miles. It speedily became known circuit, the iron will immediately fall and pash the points into as the Drummond Light, but no practical use had ever been contact again, when the action will go on as before. It is by a made of it, except as already intimated, until the establishinent combination of mechanism on this principle with clock-work, too recently of a company called the “Lime Light Company," who complicated to describe, that most of the so-called electric lamps a short time since drew considerable attention to it, by lighting are constructed.
with it the finished half of the new bridge at Westminster. With regard to the second of the desiderata mentioned, viz., the The principal obstacle to the use of the lime light, until the com. equalization of the power of the battery furnishing the electric mencement of the operations of this company, was the tendency current, this also has been accomplished in a wonderful manner. of the lime to crack and fall to pieces, under the intense heat to We have seen that magnetism can be communicated to a bar which it was subjected. This the company propose to obviata of soft iron by a current of electricity passing round it: Professor by the employment of a patented metal sheath to contain the Ersted, of Copenhagen, has discovered a remarkable circumstance lime, together with a clock-work movement, which has the effect the reverse of this, viz., that a current of electricity can be pro- of gradually bringing fresh surfaces of lime into contact with the duced from permanent magnets. By the communication of motion jets. to a wheel upon which a number of such magnets are arranged, a Tho advantagos claimed for the lime light, besides its brilliancy, current of electricity, proportionate in power to the number and are,-that it is superior to overy other artificial light in quality, size of the magnets, may be obtained. This current, to distin- and that it is less deleterious than any other light, and far more guish it from the voltaic current, is called the magneto-electric economical. Its brilliancy is beyond question; and there can be current. It is of precisely the same character as the voltaic cur. no doubt that, in quality, it is superior to any other artificial light, rent,--so far, at least, as has been at present ascertained,,but -excepting only the electric light,--as it rivals even the sun in has the advantage of continuing always uniform in intensity, the purity and power of its rays. Green and blue shades of colour however long the battery supplying it may be in action.
can be recognised and compared under its influence as accurately Notwithstanding the power and brilliancy of the electric light, as by daylight. Plants and flowers present, when illumined by it, which is identical in quality and chemical action with sun. all the brilliancy and delicacy of tint with which they charm the light, its cost, together with its lack of portability, renders it eye when seen by day. It exhibits, in fact, all objects in their scarcely probable that it can come, at least in our day, into gene- natural colours, ral use. There are, however, many purposes to which it may be With reference to its asserted advantage as being less deleteapplied with manifest advantage. It is especially suitable for rious than other modes of illumination, we may obseryo that if employment in lighthouses. Professor Faraday, in a recent lec- pure hydrogen be used, there will be no production of carbonic ture at the Royal Institution, mentioned that it had been in use acid vapour, which is given off in abundance by all lights depen. for the previous six months at the North Foreland, and had shown dant on combustion. Moreover, as the oxygen required for the thenee into France, and that never once during the whole of that lime light must be supplied in its separate state, the lime light period had it failed in doing its duty.
will not, like the lights produced by combustion, abstract oxygen Professor Wray's light, which was exhibited at Oxford on the from the atmosphere in which the light is used, thus causing those occasion of the recent meeting of the British Association for the who breathe that atmosphere to inhalo an undue proportion of Advancement of Science, and has since been exhibited at Cowes, nitrogen. As both carbonic acid and nitrogen are deadly poisons, and elsewhere, is another forin of the electric light. Instead, the limo light has certainly, from a sanitary point of view, adrane however, of proceeding from a stream of electric sparks bridging tages over such lights as are obtained by burning gas, oil, canthe interval between two carbon points, it is emitted by a very fine ales, etc. There is, however, one point to which we must refer, stream of mercury, heated to an almost inconceivable degree. with regard to the use of the lime light in private dwellinga, it Ench of what we have spoken of above as the cut ends of the con being urged in its favour that it will not injure the most costly ducting wire of the battery is dipped into a separate cup of decorations or embellishments, viz., the possible diffusion of the mercury, the one cup being placed immediately below the other, sublimed lime. Although the lime will not burn in the intense but the two cups communicating by means of a glass tube, of heat to which it is subjected, it will, neverthloss, sublime, or gra. very fine bore, one end of which passes through the bottom of the dually diffuse itself in an almost impalpable powder. Now this upper cup, while the other end dips into the mercury in the lower powder is still lime, and lime is caustic; and as caustie, or ono. By this arrangement, the electric current is made to pass "quick" lime, will “slack” when exposed to the watery vapour through the fine stream of mercury which is constantly passing in the atmosphere, in such fine particles, we should be somefrom the upper cup to the lower one, through the glass tube, and what distrustful of its effect upon a gallery of fine pictures, or upon this stream of mercury,—which ought to be finer than the point of valuable upholstery, until it had been ascertained, by a somewhat à lady's needle,- is thereby heated so intensely as to canse it to lengthened experience, that the sublimed lime was confined to give off a pale pure light at least equal in power to that which the case or lamp in which the light was used. would be obtained by the same current being made to pass We now come to the question of economy, which is one involsbetween carbon points. This light continues perfectly uniforin 80 ing a variety of considerations. To commence with, it may be long as the battery continues in action and there is mercury in the observed that, as the lime light requires the use of two separate upper cup; but it has the disadvantage of giving a most ghastly giscs, which must not be mixed, except at the jet of each separate hue to the human countenance. On the other hand, it brings out light, two lines of mains are necessary for their conveyance for certain colours,-mauve, for one, with an extraordinary brilliancy, street lighting; although it must be admitted, per contra, that as such as they do not exhibit when illumined by any other known the quantity of these gases required to ignito the lime is far light.
smaller than the quantity of coal gas requisite to produce the . We now come to the consideration of the equally powerful and same volume of light by combustion, the weight of metal in both beautiful light known by the name of the “Lime Light." This mains would probably be less than that in a single ordinary gas light, like Professor Wray's light, is not the effoct of combustion main. Next comes the cost of the gases themselves. First, the but of ignition, or that stato of incandescence which is pro- pare hydrogen. This is much more expensive than ordinary car. duced by intense heat. Except the heat produced by the arc burotted hydrogen, or coal gas. The latter, however, can be used of the electric current, the most intense heat that can be arti. for the lime light, and in fact was so used for the lights on Westficially produced, greater than that of the most powerful blast minster Bridge, but its use not only detracts from the sanitary furnace, is the heat obtained by the use of the oxyhydrogen' advantage we before mentioned, since it causes the production
of carbonie acid, but it also involves the expenditure of a much gaze on it without inconvenience to the eye. Another was moved larger quantity of oxygen than would otherwise be needed. Now about from place to place beneath the portico, and its light thrown, as oxygen is by far the dearest element used in the production by a reflector, at one time on the statue of Nelson, which it of the light, the saving of the oxygen thus wasted would pro- brought out from the dark background of the sky like a white bably more than counterbalance the difference between the price spectre; at another, on the statue of King George, whose shadow of pure and that of carburetted hydrogen. We may, therefore, was thrown as darkly and well-defined upon the facade of Morley's for the purpose of the present discussion, assnme that the one is Hotel as though it had been painted upon it in dense black. But as cheap as the other. The chief point on which the question few particulars have transpired respecting its nature or principle; of expense therefore depends, is the cost of the oxygen. The but, so far as we can judge, it most probably consists of somo small quantities in which that gas has hitherto been required method of judiciously supplying oils or other hydro-carbons with have generally been prepared from black ridd
manganese, a supporter of combustion, such as oxygen, for which they have a or, more costly still, from chlorate of potash, which, by the way, is strong affinity. It may yet possibly be capable of achicving a a substance very suggestive as regards the effect of demand on position in consequence of its portability, which, cæteris paribus, supply, for within our own memory it has been a guinea an gives it an advantage over both the electric light and the lime ounce, while it is now procurable at little more than a shilling per light. pound. The process, however, by which the Lime Light Com. pany are at present obtaining their oxygen, is one founded on
THE DEATH-WOUND OF CHARLES XII. the principle of a patent by Michele (taken out in 1853), who takes advantage of the fact that protoxide of barium, at a low
A CONTROVERSY has long prevailed amongst the Swedes as to the red heat, will absorb an additional quantity of oxygen from mode in which their illustrious monarch, Charles XII., came by the atmosphere, and will liberate such extra quantity on being his death. He was killed, the reader will remember, at the siege raised to a cherry-red heat; Michele's process consisting of an
of Frederickshall, in Norway, in 1718. The question that has been ingenious alternation of the two degrees of heat acting on the raised is, was he fairly killed at the hands of the enemy, or did
he die by treachery on his own side ? material in a closed chamber, admitting air to be decomposed, and its oxygen absorbed, when at the lower
temperature, and liberating have this question set at rest, by a careful examination of the
About a year ago, the Swedish Government became anxious to and collecting this absorbed oxygen when at the higher one. there is scarcely any loss of material in this process, the cost of the remains of the deceased monarch. Accordingly, on the 26th of
the August of last year, in the presence of the reigning king, oxygen reduces itself to that of the fuel and the labour, so that this would certainly appear to be a more promising method of obtain-Charles XV., of the great officers of state, and of a few of the ing oxygen than any previously adopted. There can be little leading physicians and surgeons of Stookholm, the royal sarco
pliagus and coffin were opened, and the state of the head, which doubt that a demand for cheap oxygen, which would be the neces. sary result of any considerable use of the lime light, would set results of this examination, and of a very long discussion which
was the seat of the fatal injury, very carefully examined. The many inquiring minds at work upon the problem; and as oxygen took place on the rending of the report of the examination to the is one of the most abundant elements with which the chemist is Swedish Society of Physicians, appeared in their journal, Hygeia, acquainted, forming one-fifth of the bulk of atmospheric
air, and in March last, and an abridgement of the account given in that nearly 89 parts out of 100 by weight of water, it is highly pro journal, from the pen of Dr. W. D. Moore, of Dublin, was pub: bable that it wil obey that law of the action of demand in the pro: lished in the Medical Times and Gazette of the 11th ultimo. duction of supply which we have already illustrated. We are not
From this we learn that an examination of the corpse was made aware whether sufficient statistics of cost, of a reliable character, in the year 1746, and that the official account of this examination have yet been obtained, to enable an authoritative statement to be is extant. It was made, however, so imperfectly as to throw no made as to the cost of oxygen in large quantities; but if, as has Ught at all on the matter at issue. been represented, it can be produced as low as eight, or even ten
When the coffin was reopened last year, the general appearances shillings per 1,000 cubic feet, the lime light can scarcely fail to be an economical one for many purposes. Like the electric light, saw it in 1746. A white linen cushion, filled with spices, lay over,
of the corpse quite corresponded with the description of those who it is admirably adapted for application to lighthouses, and it and another under, the head, -a handkerchief, however, being in would also be a most desirable light for large open spaces, such as
contact with the face. Long white bags filled in the same way, Trafalgar-square, London. If the company could put sufficient pres- lay along the sides and arms. The hands, slightly drawn towards sure on their gases to force them to the top of the Nelson column each other, were covered with white kid gloves. The shirt was there, and could get permission to erect on the top of that column of coarse Silesian linen, thé shroud of brown-holland. In the an enormous lamp globe, in place of the unseen statue, they shroud, on the left side, near the feet, was a little blue silk would confor a great benefit
, by converting that which is neither embroidered bag, tied up with blue silk, and containing a small useful nor ornamental as a monument, into the most magnificent portion of one of the metatarsal bones of the foot, which there pillar lamp in the world.
seems little doubt was a pieco removed from the king's left foot It has recently been discovered that a light, scarcely surpassed in 1709, after the wound he received at the disastrous battle of in power or brilliancy by either the electric light or the lime light, Pultowa, in which he and his forces were so completely beaten is produced by the combustion of the metal magnesium, the by Peter the Grent. metallic base of the earth magnesia. This metal is lighter even
In place of a cap, the head of the royal corpse was encircled than aluminium, is as white as silver, and does not rust. Accord with a withered wreath of laurel! The top of the head was bald, ing to a recent account in one of the scientific joumals, “it may but the back and sides were covered with thin light brown hair, be hammered, filled, and drawn out into threads; it ignites at the interspersed with grey, and about an inch and a half long. The temperature at which glass melts, and burns with a steady and face was of course shrunkon, but still showed the aquiline form of vivid flame, the ash resulting being pure magnesia ; while it has the nose. The upper-lip was somewhat retracted; the eyelids been found experimentally that a very fine magnesian thread slightly open; the skin parchment-like, and of a greyish-yellow, emits a light equal to that given by seventy-four stearine candles or, in places, greyish-brown. The expression worn by the features of five to the pound. These peculiar properties have suggested was very calm and solemn. the possibility of using it for illuminating purposes. To effect
The centre of the forehead was disfigured by a depression, this, it is only necessary to devise some mechanical means of found afterwards to correspond with a fracture of that part of the spinning the metal into thread ; when this is attained, we shall bone of the skull. On each temple was a black velvet patch, have a light more simple and efficient than any yet used, whether adhering by means of something spread on the wrong side of the electric or lime. The illuminating power may be increased to velvet. Beneath these were the holes in the skin through which any estont by adding to the size of the wick, the only requisites the fatal missile haul passed. That in the left temple was the to light being the magnesian thread, a clockwork arrangement to larger of the two; so, also, the opening in the bone was of much supply it continuously as used, and a spirit lamp. Costly as greater extent on that side than on tho other, the margin of the left magnesium is, more economical modes of producing it will doubt-arbit or eye-socket having been completely carried away. The lens be suggested by the demand for it. It seems also that the bones around the openings were much comminuted, and lines of magnesian light will be specially valuable in photography, since, fracture extended from them, both on to the forehead and into the according to Bunsen, the sun has only thirty-four times its photo- base of the skull, while the base of the skull itself, corresponding chemical power."
with the cavities of tho nose and top of the throat, was broken into Another light which has recently attracted some attention is many fragments. Besides the rags and spices used in the process the "Fitz-Maurice Light," so called from its having been intro- of embalming, loose portions of bone, and also the dried waxy duced by Captain Fitz-Manrice. Its chief advantage is stated to be remains of the once regal and active brain, were discovered within its portability. It was exhibited in Hyde Park abont a year ago, the cranium, bat no trace of shot or other missile was found. and also at Trafalgar-square, at which latter place we had the On carefully noticing the extent and character of the injurios tr. opportunity of observing it. It is a lightapparently equal in quality the bones, the direction of their broken margins, and so forth, to the limo light. One, enclosed by a ground-glass globe, illumi. the examiners were of opinion that the missile, which was evirated the roadway opposite the National Gallery 80 that one dently from some kind of gun, hau passed throngh the king's could see to pick up a pin on the further side, while it was so soft head from left to right; that, although nothing could be decided and subdued by the ground-glass as to permit the spectator to with regard to the exact nature of the missile, it was probably a musket or a grape-shot, ---less probably, though still possibly, some were like luminous clouds; others were in the form of a case shot, or fragment of a bursted bomb-shell; that it must streaks, more or less curved; one was shaped like a ketile; have been fired from a distance, its velocity having been evidently another like a ship in full sail, and one, a very remarkable coe, is partly spent before it struck the king ; that its path, as indicated by described as shaped like a boomerang. The dimensions of some the injuries to the skull, was probably from a point higher than of these luminous projections are truly astounding, their breadth the spot on which the king stood at the moment he was hit, --being often 28,000 miles, and their length varying from 42,000 to although the appearances on which this conclusion was founded 56,000 miles.* So far as observed by Mr. De la Rue, they were might have been occasioned by the king's head being inclined at not at any one time arranged in the regular, continuous, “Bailey's the moment; that the wound must have been instantly fatal; and Beads" fashion; but another observer describes them as at one lastly, that there is no evidence that his majesty was struck by moment presenting, on the south-western quarter of the moon's more than one missile.
edge, the appearance of a long continuous row of golden' promis In the discussion which ensued, some difference of opinion arose nences. It is curious that the boomerang protuberance, although as to which side of the head the missile had entered at; but all photographed distinctly, was invisible to the eye. Tiás, Mr. Agreed that Charles XII. did not fall by the hand of one of his own De la Rue suggests, may be owing to its having possibly been followers. The Swedish name is thus completely freed from the of a faint purple tint. Mr. De la Rue expresses no opinion as to slur which had been cast upon it by the suspicion that this illus- the nature or causes of these curious protuberances, or as to their trious monarch had owed his death to foul play.
relation to the sun or its atmosphere. We may add that the report of the examiners, as published in The general phenomena of the eclipse, as observed in Spain, the Hygeia, is illustrated by five interesting plates, showing :- were in harmony with what is recorded of the phenomena of 1. The royal corpse in the coffin, with the wreath of faded laurel former total eclipses. The indigo hue of the sky, lowering into around the head. 2 and 3. Right and left views of the head, orange at the horizon,—the dark blue of the mountains,—the deep showing the holes in the integuments. 4 and 5. Two views of shadows,-the bewilderment of birds and beasts,-the quietude of a skull, on which (what a curious fate, could the owner have foreman, all combined to give to nature a deep solemnity of aspect seen it!) the injuries to the king's head have been imitated. scarcely conceivable by those who have not themselves actually
witnessed a total solar eclipse,-the obscuration caused by which
is many times greater than that occasioned by the largest partial THE LATE SOLAR ECLIPSE.
eclipse. There are but few persons who have witnessed a total
solar eclipse, only two solar eclipses having been total at London TAB most interesting account of the recent eclipse of the sun
since the Norman conquest. The first of these occurred in the which has yet been published, is that given in the letter from Mr.
year 1140, the other in 1715. Eclipses of the sun, total in some Warren De la Rue which appears in the Times of August the 9th. parts of Europe, will occur on the 31st of December, 1861, in 1870, Mr. De la Rue is one of the astronomers who went to Spain to in 1887, and 1896; but the next solar eclipse total at London will not observe the eclipse, Spain being the only part of Europe in which take place until some years after the commencement of the the eclipse was total.
twentieth century. By means of an instrument called a Photoheliograph, Mr. De la Rue succeeded in obtaining, at various stages of the eclipse, some valuable "sun-pictures” of the sun itself. This instrument was THE COAL AND GUANO DYES.-MAUVE, MAGENTA, ETC. originally designed by Mr. De la Rue, at the suggestion of Sir It is now nearly sixteen years since Mr. Murdoch astonished the John Herschell, for the Observatory at Kew. It consists of a people of Birmingham by illuminating the front of the great manupyramidal tube, fitted with two combinations of lenses, and with factory of Boulton and Watt, at Soho, with gas produced from conveniences for the introduction and exposure of sensitive plates. coal. What had hitherto been an idle dream, becamo a recognised The sensitive plates are introduced at the larger end of the tube, fact, and the practicability of lighting the streets of large towns by the object glass being at the smaller end. The primary image of means of coal-gas was not long in being established. Since then the sun, formed by the object glass, is not quite half an inch in the science of chemistry has made immense progress, and has diameter ; but before this image falls on the sensitive plate, at the found amongst the products of the distillation of coal substances of larger end of the pyramidal tube, it is enlarged, by means of which the value had hitherto been unknown. Amongst these is secondary lenses, to a diameter of nearly four inches. So rapid is the liquid from which aniline is prepared, and which in its turn the action of the direct solar rays, that, in taking photographs of yields the magnificent dye known as "mauve." Nor is the source the sun, it is requisite that they should not be allowed to fall on of the dyes known as “fuschine” and “ magenta" any less the sensitive plate for more than a very small fraction of a second wonderful. They are obtained from "murexide,” which is derived of time; and this is managed, in the case of the photoheliograph, from uric acid, while the uric acid of commerce is derived from in a very ingenious way. In front of the sensitive plate is an guano. opaquo slido, in one part of which is a very narrow slit. This When coal is submitted to distillation in large iron retorts, its slide is held, with the slit out of the line of light, by a loup of complex bituminous constituents are resolved into bodies of mora thread, which being, at a given signal, set on fire, the "slide simple composition. These are gaseous, liquid, and solid, flashes instantly across the axis of the instrument, allowing the The gasoous products are hydrogen, carbonic oxide, carburetted sun's rays to pass momentarily through the slit on to the sensi. hydrogen, olefiant gas, sulphuretted hydrogen, carbonic acid, tivo plate," upon which the sun's image is thus fixed almost cyanogen, sulphoryanogen, sulphurous acid, hydrochloric acid, instantaneously.
nitrogen, and vapoor of bisuphide of carbon and water. Only Altogether, during the progress of the eclipse, Mr. De la Rue the four first-mentioned gases are combustible; and therefore, in caused thirty-one photographs to be made. The time at which the manufacture of gas for illuminating purposes, all the others each was taken was accurately noted, a most valuable record for have to be removed. By passing the mixed gaseous products as the verification of astronomical calculations being thus formed. they proceed from the retorts through milk of lime, all the nonSo long as any portion of the sun's disc remained unhidden by illuminating gases and vapours are removed as completely as the moon, the photographs were taken in the manner above possible. Of the four illuminating gases, only the oleflant gas indicated, but as the totality approached, and a longer exposure possesses any considerable luminous properties, so that the quality became necessary, the slide apparatus was no longer employed ; of the gas supplied for lighting purposes is always estimated by a stop hitherto used at the object end of the photoheliograph was the percentage of olefiant gas which it contains. removed, so as to admit more light; and the instrument was put 2. After all the volatile products have distilled off, common coke into connexion with the necessary clockwork, and thus made to remains in the retort. If the sides of the retort have been overmove so as to allow for the motion of the earth. A very success heated, and this happens rather frequently, part of the gaseous ful photograph was then obtained by one minute's exposure. and liquid products are decomposed, depositing an exceedingly
The most interesting astronomical phenomena attending a total hard crust of carbon on the retort. This carbon has been advaneclipse of the sun are the formation of a luminous halo, or “corona,” tageously substituted by Bunsen for the platinum element of Grove's around the darkened body of the moon, and the appearance of battery. certain brilliant luminous protuberances at and near its edge. 3. The liquid products consist of water containing ammonia These protuberances, when numerous, regular, and connected and ammoniacal salts, which are either used as manure or emtogether, constitute what are called " Bailey's Beads." Mr. De la ployed in the preparation of salts of ammonia, and a thick semiRue, on the recent occasion, succeeded in photographing the liquid substance called gas tar. The nature of this tar was forluminous protuberances at certain stages, and also that part of merly so little understood that it was burnt as fuel under the gas the corona nearest to the moon's disc. The corona appeared first retorts! The constituents of coal-tar are exceedingly numerous, on the eastern, or advancing, edge of the moon, and then, as the moon glided onward, on its western edge, so as to constitute a
• These are the dimensions given by Mr. De la Rue. M. Petit, however, the completo halo. It was white, and radiated in all directions, in a director of the Observatory of Toulouse, has published a measurement of some manner reminding the spectator of the aurora borealis. The of these protuberances, according to which some of them were not less than luminous protuberances, which were very numerous and variously 20,000 leagues wide, and 80,000 leagues long. M. Petit regards them as being shaped, were much more brilliant than the corona. Some of
not mountains, but enormous clouds, floating in the vast atmosphere of the
sun. He declares that two of them which he observed were separated from tdt thern were white, others golden others of a faint rose colour, | disc of the sun by an interval of at least 6,000 leaguas
and many of them have not yet been completely investigated ; it until it becomes saturated; it dissolves out carbonate and oxalate will be sufficient to enumerate the most important,
of ammonium, phosphate and carbonate of calcium, etc., and is 1. Carbolic acid or phenylic alcohol.–This body may be sepa therefore extremely valuable as manure, or for preparing phosrated from the coal-tar by means of lime. In its impure state it is phates of ammonia. The residues are again weshed with fresh liquid, and goes by the name of creosote, of which the uses are well quantities of warm hydrochloric acid, and finally with water. known; when perfectly pure and free from water, it is a beautiful They consist of uric acid mixed with small quantities of sand and white crystalline body.
clay. II. Ammonia, and various alkaline bodies resembling it, viz.,- When uric acid is added by small portions to nitric acid of sp. picoline, quinoleine, pyrrol, and aniline.-Aniline may sometimes gr. 1. 4, care being taken to wait each time till all effervesconco be extracted from coal-tar, but it is generally present in too small has ceased before adding a fresh quantity of uric acid, a substance A quantity to be obtained advantageously from this source. called alloran is gradually deposited from the liquid in small
III. Various compounds of carbon and hydrogen, both liquid granular crystals, which must be separated from time to time and solid, viz., liquid,-benzin, toluene, cumene; solid, -napthalin, from the acid mother-liquid. The crystals are drained from acid, chrysene, and pyrene. Of these bodies the most important is dissolved in water, the solution is kept near the temperature of benzin, which is extracted in the following manner :-The coal-tar ebullition, and a solution of carbonate of ammonium added drop is submitted to fractional distillation, and the more volatile distil. by drop. Carbonic acid is evolved with effervescence, the liquid Jate is set aside from the heavy oil, which remains in the retort.
assumes an intense purple colour, and finally becomes thick, This last is principally used for preserving railway sleepers and owing to the deposition of reddish brown crystals of murexide. wood which is exposed to decay, on account of its powerful anti-Carbonate of ammonium is still added, till the liquid smells septic properties, due principally to creosote. The light oil contains feebly of ammonia ; the mother liquid is then decanted, and the benzin, toluene, cumene, etc. If this be distilled, and the product crystals are washed with water till the wash waters become of passing over at about 176,5 deg. Fah. be collected apart, all the ben- a deep purple colour. zin will be obtained, and may be purified by rectification. Toluene, Murexide may also be prepared by directly adding ammonia, in which has the next lowest boiling point, does not boil till 237 deg. small portions to avoid heating, to the solution of uric acid in nitric Fah., so that the separation is almost complete. Pure benzin is a acid. The liquid deposits crystalline murexide on cooling. This limpid, colourless oil of rather agreeable odour. It is lighter than method, however, only succeeds under certain conditions, the water. Submitted to the cold it solidifies in crystalline laminæ. exact nature of which is not well known, It is extensively used for dissolving gutta-percha, for manufactur- Murexide crystallizes in transparent flat four-sided prisms. ing varnish, for cleansing clothes, gloves, etc., from grease, as a These crystals appear by transmitted light of a fino garnet-red combustible for lamps, and finally for making nitrobenzin, from colour; by reflected light they appear on the two broad sides of which aniline is prepared.
the prism of a magnificent golden green, like the wing cases of a When benzin is added in small quantities to warm fuming nitric golden beetle, while the narrow sides are reddish brown, or, in a acid, the liquid, on cooling, deposits nitrobenzin as an oil. The strong light, greenish. Their powder is red, and under the bur. product is washed with water and carbonate of soda, and recti- nisher assumes a green colour, of a metallic lustre. Murexide is fied at 415 deg. Fah. Nitrobenzin is a yellowish liquid, of but very slightly soluble in water, to which, nevertheless, it sweet taste and highly agreeable odour, resembling oil of bitter imparts a magnificent purple colour. In potash it dissolves with almonds, for which it is most economically substituted in per intense blue colour, forming purpurate of potash. fumery, and sometimes in pastry.
Murexide furnishes brilliant carmine, purple, orange, or yellow When nitrobenzin is acted upon by zinc filings and sulphuric dyes, according to the mordant or metallic salt with which it is acid, or by sulphide of ammonium, it is converted into aniline. employed. Carmine or purple tints are best produced by using Aniline was discovered, in 1826, by Unverdorben, and named by salts of mercury as mordants, and orange or yellow by salts of him crystallin. It was subsequently investigated by Runge, who zinc. A purple colour is imparted to silks by steeping and concalled it kyanol, and by Fritzsche, from whom it received its present stantly stirring the fabric in a mixture of solutions of murexide name. It may be prepared in a variety of other ways; for instance, and corrosive sublimate. The tint varies in intensity according by heating indigo with potash. Aniline is a colourless liquid, to the strength of the bath and the time the fabric is immersed. heavier than water, of a strong aromatic odour, which is not dis. The dyeing of woollen is attended with more difficulties, since agreeable when it is pure. It is but slightly soluble in water. It the wool exercises a reducing action on the murexide; it is necescombines with acids, and forms salts, just like potash and soda, sary to employ corrosive sublimate and oxalic acid, or sulphate of and belongs to the class of bodies called alkaloids, such as nicotine mercury and tartrate of potassium and mercury, with the dye : from tobacco, and closely resembles ammonia. Indeed its formula and to these an oxidizing agent, such as chlorine water or bleachis represented by ammonia (which consists of one atom of nitro. ing powder, must be added. The woollen is finally dyed with a gen and three of hydrogen), wherein one atom of hydrogen is solution either of pure murexide or of murexide and oxalate of replaced by one atom of a compound radical, i.e. a compound body sodium. playing the part of an element. The radical in this case is phenyl, Another method consists in immersing the fabric in a colourless å compound of carbon and hydrogen. We are indebted to an solution of uric acid in nitric acid, and exposing it to heat in & English chemist, Mr. W. H. Perkin, for the discovery of the aniline current of hot air, or over a healed metallic surface, and finally dye. It is prepared in the following manner :-Impure commer. fixing the colour by means of a bath of either mercury, or zino cial sulphate of aniline is disolved in water and mixed with a salt. certain quantity of solution of bichromate of potassium, and the Murexide, it appears, is also capable of forming "lakes" almost whole is allowed to stand for ten or twelve hours. The black, insoluble in water, and possessing very vivid tints. pulverulent deposit thus obtained is thrown on a Alter, washed Such, then, is a slight sketch of the methods by which these with water, dried at 212 deg. Fab., and finally digested with coal magnificent dyes are produced in such a wonderful manner from or naphtha to dissolve out a brown resin which is always present. substances with which their connexion would appear at first sight The colouring matter is now dissolved in wood spirit, which, by incredible. gentle evaporation, deposits the dye in a state of purity. To dye stuffs of a lilac or purple colour, a strong alcoholic solu.
PICKLING AND POISONING THE THAMES. tion of the dye is added to a weak boiling solution of tartaric or Tax condition of the Thames this summer, owing to the rain-fall oxalic acid, and when tho liquid is cold, the silk or cotton fabric having been more than double what it was in 1859, and larger still is immersed in it.
in comparison with that of 1858, has been unusually pure. In the To dye woollen, it is better to add sulphate of iron to the liquid, month of June its water contained, at the most, only thirty-two and then to boil the whole. The fabric is washed, first with pure grains of dissolved substances per gallon, of which from two to water, and afterwards with soap and water. The aniline dyes are four grains were organic matter; whilst last year, at the same characterized by their great beauty and durability, and at the time, it contained ninety-four grains, and the year before one hunsame time by their colouring powers, very small quantities being dred and forty-three grains per gallon, of which from eleven to sufficient to dye a large amount of material.
twelve were organic matter. In August and September of that Murexide, or the guano dye, was so-called by Liebig from its year, the impurities it held in solution amounted to from three probable identity with the ancient Tyrian purple, which is sup- hundred to four hundred grains per gallon, and it was most horribly posed to have been prepared from & shell fish named murex. offensive. Scheele discovered, as early as 1770, that the solution of uric acid Whenever the river-water contains an unusually large amount in nitric acid reddened the skin, and left & purplish-red residue of dissolved impurities, the excess is found chiefly to consist of on evaporation; but Prout, in 1818, first prepared crystalline common salt and sulphate of soda, as if, in the absence of upland murexide, to which he gave the more appropriate name of pur. foods, the tidad sea-water penetrated far up the river ; but there purate of ammonia. It has since been investigated by Liebig, and is also to be taken into account the fact that the contents of the Wohler, and others. To preparo murexide, it is first necessary sewers discharged into the river are much concentrated, or but to obtain uric acid. For this puposo guano, in which uric acid is little diluted, in comparatively dry seasons. It has been supposed, contained as urato of ammonia, is digested with dilute hydro- indeed, that it was this direct admixture of an undue proportion chloric acid; the solid residue is then allowed to settle, and the of sea-water with sewage water, both in an unusually concen. clear liquid decanted. This liquid is again applied to fresh guano trated state, and acted upon by a high temperature, which led to the noisome decomposition noticed in recent years in the valueless, and was trodden under foot by the careless native, and Thames. How far such a conclusion is in favour of, or militates regarded by the unconscious colonist as of no more worth than against, a plan for the purtfication of the Thames, which has been the materials of which ordinary sea-beaches are composed. suggested and patented by a Mr. Kotulla, we are not prepared to To-morrow, it will be knives, needles, chisels, swords, bayonets, decide. This method consists in increasing the specific gravity of gun-barrels, implements of peace or weapons of war, and will the river-water by dosing it with common salt in large quantities, be bought and sold for many pounds per ton. Bo that, either becoming of the same density as sea-water, it will The origin of this wonderful tract can only be conjectured. The easily intermix with it, or, becoming heavier, it will run away supposition which has most to recommend it is, that volcanoes beneath it, at all times, instead of, as low, being lifted up and hela containing pure steel in a state of fusion must have existed near back by the marine supply. He farther advises the addition of this spot; that the sea at some time broke in upon the molten half a ton of alum to every one hundred tons of salt. The dosing mass; that an eruption was thus caused which sent enormons he recommends to take place at the ebbing tide, to be continued clouds of metallic particles into the air ; that these particles fell for a few days at first, and then only occasionally, as required. back into the sea, and have thence been washed on to the shore,
But what follows is of more startling interest. A short time layer after layer, itil the present vast beach has been formed. since it was recommended, for the purpose of deodorizing the Nothing resembling these metallic particles is known to exist London sewage, or the Thames itself, to add to it in certain quan- elsewhere in nature. The native steel which is found at times in tities a particular solution of perchloride of iron, patented by a mining, and which differs materially from ordinary iron ore, con. Mr. Dales. Dr. Letheby has found that certain samples of this stitutes the nearest approach to them. It occurs in the shape of solution contained two hundred and ninety-six grains of chloride " button ingots" with a finely striated surface, and is supposed to of arsenie per gallon! So that for the purpose of complete have been produced by "the spontaneous combustion of seams of deodorization no less than two hundred and twenty-seven pounds coal in the neighbourbood of ferruginous deposits," --the burning of that highly poisonous substance would be poured, with the per- scum acting as a smelting-furnace, the adjacent ore being chloride of iron solution, into tho Thames every day. The quantity smelted in it, and the natural steel thus formed having gradually necessary for one million gallons of sewage would contain enough cooled, assuming the rounded form, whence the name, “button arsenic to kill two thousand six hundred and forty porsons; and, ingots." Something of the same sort is what is supposed to have seeing that eigiity millions of gallons of sewage enter the Thames taken place with the Taranaki metal; except that, instead of the every twenty-four hours, Dr. Letheby thought it right to "tarn Taranaki metal having tranquilly cooled, the breaking in of the against the use of so frightfully dangerous a liquid."
sea is supposed to have caused a sudden interruption, and a violent However, the most timid Londoner need not take alarm. Drs. explosion, which burst the metal into comminuted particles. Hoffman and Frankland find that the samples of perchloride When this steel-sand is placed in a crucible or retort, and examined by them contain only one hundred and twenty-five reduced to a state of fusion, it can be immediately moulded into grains of chloride of arsenic in the gallon; but, what is of moro ingots of steel. For it is not simply iron requiring to be manufacconsequence, they show that if the quantity wore always what tured into steel, -it is ready-made steel. Dr. Letheby found, it would be rendered innocuous by being In order to a due appreciation of the value of the Taranaki mixed with the sewage matter. Sowage matter is highly alka- sand, it is necessary to understand the process by which iron line, and, when mixed with tho perchloride of iron solution, gives is converted into steel. Steel is iron chemically combined with rise to a precipitate of the hydrated peroxide of iron, which is the carbon or charcoal. There very often exists a mechanical mixture most complete antidote for arsenic with which we are acquainted, of carbon with iron; but for the making of steel a more subtle, instantly uniting with it to form an absolutely insoluble and because chemical, combination of the two elements must take innocuous compound. In fact, sewage-water so treated and then place. This is accomplished by the process of "cementation." filtered, contained not a trace of arsenic, nor even of iron itself. The difference between iron and steel may be easily perceived The use of the perchloride to deodorize the sewage in filtering by comparing the places of fracture of a broken bar of each. The réservoirs by the side of the river, and then allowing the purified former will be found to present a fibrous, and the latter a grann, water to pass into the stream, could, therefore, do no possible lated or crystalline structure, The difference in character ia harm to the river-water.
even greater than that in appearance; it is the difference between But, moreover, suppose the solution to be thrown directly into a piece of iron wire and a needle of the same thickness; o the Thames, there would then be only one grain of arsenic fren between a piece of iron hoop, and the fine Damascus sword-blades, dered insoluble by its union with the iron) in three thousand grains so famous in history and oriental romance, pliant enough to be of the solid sewerage substances. This, if diluted by the whole twisted into a knot, tough enough to be driven through a water of the river, would assuredly do no harm. But, suppose it helmeted head, and keen enough to sever the lightest fabric. were all dissolved, and, therefore, in a stato ready to act poisonously, For the process of "cementation," the best iron ores are still, as one thousand millions of gallons of water pass through chosen, and certain districts are celebrated for yielding good London daily, there would be only one grain of white arsenio in steel iron, such as the Danemara, about thirty miles from Upsal, in one thousand four hundred and fifty gallons. The water at Wies. Sweden, the Wootz in India, the Forest of Dean and Ulverstone, baden, taken by invalids, contains one grain of white arsenic in in England. The oro having been smelted and converted into one hundred and sixty-six gallons. Suppose, therefore, an indi. soft iron bars, these are buried in some carbonaceous substance, vidual to consume even a gallon of water daily in beer, bread, and usually wood-charcoal, the whole is tightly compacted together, other food, it would take him ten years to have imbibed aand covered with clay so as to exclude the air, The furnace in poisonous dose; and it would take three and a quarter tons of which they are placed is then fired, and continued at a given heat coal to evaporate enough of old Father Thames to yield the lor a certain time. During this heating, carbon is gradually same poisonous dose.
absorbed by the iron, until throughout the substance of the bars a It is obvious, therefore, that this arsenicophobia is without crystalline formation takes the place of the preceding fibrous foundation. Perchance the introduction of small quantities of arrangement. When the bars are drawn from the furnace, they arsenic into the Thames might even do good, in the same inscru. are covered with blisters, or air-bubbles; hence they are named table way as the arsenic fumes, produced in brass-founding, "blistered steel.” In this state the steel is fit for the manufacture have been thought, perhaps, to account for the remarkable free of rough articles; but other processes are necessary to perfect it dom of Birmingham from cholera in its several visitations to either as "shear-steel" or "cast-steel.” For the former, the bars this country.
are submitted to continual "tilting" or hammering, to attenuate
them into rods, which are then clamped into bundles, hcated, and THE STEEL SEA-BEACH OF TARANAKI.
then hammered again into an homogenous mass. For cast-steel As instance, as remarkable as any which could be named, of the the blistered ingots are broken up into fragments and placed in discovery of the true character of some useful product of nature, retorts of Stourbridge fire-clay. Great care is taken in making after its having lain long unknown and unemployed by man, these retorts. The clay is trodden out by the naked feet, by the though close beneath his hand, has just occurred in the district sensibility of which grits and air-holes are detected, and got rid of Taranaki, near New Plymouth, in New Zealand. For about of. With the steel fragments is mingled a little manganese, and seventeen miles along the coast of this district there is nothing to the mouth of the vessel is closed with bottle glass, which melts be seen but a dull smooth beach, of a dreary black hue, which is in the fire and hermetically seals the retort, These charged deepened by contrast with the snowy foam. This beach is half a crucibles or retorts are placed in a furnace, and the steel mile wide at low water, and its constituent particles or grains have molted, and poured out, in the form of a glowing fiery liquid, å slight metallic lustre, and are 60 small as to resemble fine into moulds. The ingots thus made are then ready for forging gunpowder. They are much heavier than ordinary sand, whence into any of the thousands of articles for which such metal is used. the beach is very much smoother than our own sandy sca-boards. The tempering, which is done by heating the manufactured So smooth and glassy is it, that nothing that the waves can wash article and suddenly cooling it, is an after process, regulated by on to it can remain on it. Its black monotony is therefore the degree of hardness required. unrelieved by shells or sea-weed,-much to the increase of its From this indication of the labour and expense involved in drenriness of aspect.
making iron into steel, the peculiar characteristics and valtio of the Strange to say, this long and naked strand consists of myriads Taranaki sand will be readily understood. It has merely to be of tons of steel, in a granular form,-pnre, excellent steel, of fused, aud may then forthwith be moulded into bars ready for very fine quality. Yesterday this black dust was thought to be forging. It does not require to undergo any of the intermediate