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a small Siemens armature. The coils of this paper be uniform. Some experiments were electro-magnet are traversed by the current made with siliceous diaphragms. Columns of produced by the rotating armature, after being, sand, varying from five millimetres to five by means of a commutator, made to flow in centimetres in height, kept in position in each one direction only. At the commencement of case by a tuft of asbestos, were substituted in rotation, the armature is acted upon merely by a former apparatus. In operating in Dutrothe weak residuary magnetism of the electro- chet's way, with solution of sugar, solution of magnet, and consequently only weak currents salt, and distilled water, simple filtration took are produced in its surrounding coil. These place, instead of a strong endosmose with the weak currents, passing through the coils of the organic membrane; but this was not the case electro-magnet in the same direction, instantly when a saturated solution of sulphate of soda increase the residuary magnetism, thereby was placed in the tube, and in the outer vessel again producing increased induction currents another of chloride of barium, an endosmose in the armature, and so on until the iron of the of two centimetres resulting in two days. No electro-magnet has taken up the highest precipitate is seen in the outer vessel, so that amount of magnetism which it is capable of there is only a displacement of the solution. holding. In this arrangement the coils are In placing in a tube closed with a diaphragm short-circnited, and so kept during the revolu- of parchment-paper a solution of sugar or of tions of the handle when current and magnet- salt, colored with litmus or other coloring ism are developed to their utmost extent. By matter, and water in the outer vessel, a strong now suddenly opening this short circuit a very endosmose is produced in the tube, and at the powerful current of short duration (expressly end of a few days traces of color in the water adapted to blasting purposes) will pass through are only seen with difficulty; the color is coma line connected to the terminals. The in- pletely arrested by the membrane. strament is claimed to be handy, portable, An Improved Voltastat.-Professor Guthrie and useful in all weathers, having a superiority has exhibited to the British Chemical Society over galvanic batteries and also over static- an improved Voltastat by which the current electric machines, which only act in fine of a galvanic battery may be maintained perWeather. The instrument may be actuated fectly constant and regular by a self-acting either by magnetism or by a current from a arrangement, which is thus described : A versingle cell. After that there is always suffi- tical glass cylinder of about the size of a test cient residuary magnetism to induce a weak cur- tube is charged with dilute sulphuric acid, rent in the armature; and thus a never-failing with a layer of mercury below occupying sapply of electricity is at command for the about one-third of its total contents. Partly object required. In blasting operations it is immersed in the acid liquid is a pair of said to work with great success. It is also platinum electrodes insulated by glass fused adapted for the release of clockwork or signal upon the wires at that portion which passes bells for railways, and for the sending of cur- through the cork stopper of the jar, and a rents in rapid succession into a line of tele- comparatively wide glass tube open at both graph,

ends is fixed in the same cork, with its lower Électro-capillary Paper.-M. Becquerel has extremity dipping below the level of the merinvestigated certain electro-capillary phenome- cury, while another delivery tube with bulb Da, and describes the process and results as and capillary orifice provides for the slow esfollows: He prepared parchment-paper with cape of the mixed gases resulting from the ordinary filter-paper by immersing in sulphuric electro-decomposition of the water. This apacid, containing fifteen per cent. of water, with- paratus having been placed in the battery cirdrawing immediately and washing with a large cuit

, say of three Bunsen cells, evolves the quantity of water. A tube closed by a dia- oxyhydrogen gas with a rapidity which may phragm of this material, and filled with a be easily regulated by the size of the aperture; saturated solution of nitrate of lime, was if, then, the activity of the battery is increased, planged into a solution equally saturated with the larger volume of gas, unable to escape, solphate of soda. Stalactites formed on the erts a greater degree of pressure upon th ander surface of the paper, composed of crys- liquid contents of the cylinder, and the mertallized double sulphate of soda and lime. cury is forced up the open tube, whereby the These stalactites are of variable diameter, column of liquid descends and smaller surfaces Farying according to the size of the pores of the platinum plates are left immersed, and which allow the passage of the nitrate of lime. the power of conduction is to a corresponding By diminishing the size of the capillary tubes, extent lessened. In this manner the author the passage of the liquid is indefinitely re- states that he found no difficulty in maintaintarded, until it at length becomes inappre- ing a perfectly uniform current for a period ciable. There is a point, in regard to the of six or seven hours, and any required adjust-, diameter of these capillary tubes, where the ment could be made by altering the size either' electro-capillary force ceases to act, and where of the apparatus or of its component parts. complete filtration ensues; a single pore is By collecting the gases evolved, this little arsufficient to produce this effect. For this rangement could also be made to serve as a reason it is necessary that the parchment voltameter. The president of the society, Mr.

Warren De la Rue, in remarking upon the nizable as those described by different authors ingenuity displayed in the construction of the as characteristic of calcium, but their number apparatus, suggested that, while it would be and intensity is greater and they are better defound serviceable in electro-plating and other fined. This is not surprising if the difference applications where a somewhat intense current between the luminous intensity attainable by was employed, he doubted its use in the ordi- this process and by those hitherto employed nary electrotype process for the deposition of be considered. It would be doubtless possible copper, where weak currents only were re- by this method to obtain much new informaquired.

tion respecting the spectra of metals, provided A New Exciting Liquid.-In a note to the only pure products were employed. French Academy of Science, M. Delaurier men- The employment of strontia gives analogous tions a new exciting liquid for galvanic batter- effects under the same conditions, the light asies. He says that, in order to obtain very pow. sumes a characteristic red tinge, and the specerful batteries disengaging no deleterious gas, troscope displays the rays characteristic of and of very cheap maintenance, he has solved strontium, thus presenting a simple means of the problem of transforming azotic acid into enriching the electric light with red rays. It sulphate of ammonia, under the in ence of may be here remarked that the flame always sulphuric acid and hydrogen. This he does by contains a largo proportion of white light, for the agency of protosulphate of iron; the pro- if the metal be set free in some parts of the portions are twenty parts of the protosulphate flame, in others it returns to the state of oxide, dissolved in thirty-six parts of water (the op- the incandescence of which always yields a eration being sheltered from contact with the white light. air), to which are added, with stirring, seven Color-effects of Electric Discharges. — The parts of diluted (equal parts) sulphuric acid, and American Journal of Science for May, 1868, then in the same manner one part of diluted contains the substance of a paper, read by M. (equal parts) azotic acid. He says that the re- Becquerel before the French Academy, on the sulting liquid is the most energetic and most effect of coloration presented by discharges economical that he knows for an exciting from an inductorium taking place between the liquid for iron, zinc, and other metals without platinum wire and the surface of a liquid. The any disengagement of hydrogen or binoxide of apparatus employed by the author was very azote. In the use of this liquid with nitric simple, consisting merely of a glass tube, partacid in Bunsen's pile, the action goes on with- ly filled with a saline solution in contact with out any exterior emanation of nitrous gas, and a platinum wire forming one pole of an indacwithout the emission of hydrogen in the inte- torium. The other pole was formed by a plarior, and consequently the platinum does not tinum wire, the extremity of which was placed polarize.

a few millimetres above the surface of the Decomposing Action of the Voltaic Arc on liquid, the discharge taking place between the Certain Substances.- Mr. F. P. Le Roux, in a liquid and the wire. In case the inductoriam is paper in the London Chemical News, offers evi- of low power, coloration is not observed when dence to show that the earthy and alkaline- the liquid is positive and the wire negative, but earthy oxides undergo a real decomposition only when the wire is positive. But when the in the voltaic arc. If a cylinder of magnesia, coil is powerful, and the salt dissolved easily or lime, or strontia, be fixed in the voltaic aro, a vaporized, coloration is observed in either case, slight cavity instantly forms at the base, and though the maximum is given when the wire the conditions remain the same for an indef- is positive. With a sufficiently powerful coil, inite time; the arc continuing to play upon the the luminous effects of the discharge are very body without inducing any change but the vitri- brilliant. The spectrum of the light produced fication caused by the siliceous vapors emitted in this manner is more complex than that reby the impure charcoal. If, however, the cyl. sulting from the introduction of small quantiinder of earthy matter be brought into actual ties of saline matter into a non-luminous flame. contact with the charcoal points and the press- The water is vaporized and we have lines due are maintained with a slight spring, different to oxygen and hydrogen; the temperature is results follow. If a pencil of lime, or even also higher than that of the flame of a Bunsen's plain chalk, be used, the carbons will hollow burner. With very pure water the intensity out in it a sort of trench in which the heat is of the discharge is feeble and the spectrum concondensed as in a sort of reverberatory furnace, tains the red and blue hydrogen line correand the amount of light emitted is proportion- sponding to the dark rays O and F of the solar ally augmented. On examining the light with spectrum. With a strong solution of chloroa piece of black glass it presents the appearance hydric acid in water the tint of the discharge of an opaque luminous cloud in which the ex- is slightly violet and the two red and blue rays treme ends of the charcoal are undistinguish- are more distinct than with water. There are able, their usually well-marked brilliancy be- also an orange band and a few fainter rays ing lost in the mass of light, and there is a throughout the extent of the spectrum. A very sensible evolution of whitish fumes. The spec- small quantity of saline substance in water is troscope displays an intermittent spectrum filled sufficient to communicate to the light of the with large and brilliant rays, which are recog- discharge the color due to the elements of the salt. Thus water containing one one-thou- the figures from the two diapasons being presandth part of its weight of chloride of strontium cisely similar, in consequence of the metals begives very distinctly the orange and blue rays ing in unison. Round one diapason was then characteristic of strontium. With concen- placed a powerful bobbin of wire, actuated at trated solutions the effects are more marked, and will by a current from eight Bunsen's elements. with the chlorides in particular they are very The other diapason was left unchanged. Imbrilliant. Thus the chlorides of strontium, cal-mediately on passing the current through the cium,

sodium, magnesium, copper, and zinc, give bobbin, exciting the diapason, and rendering it fine effects. But other substances, such as vari- magnetic, the following changes were noticed ous compounds of barium, potassium, antimony, in the figure reflected from it in the mirror: iron, manganese, silver, uranium, etc., give ef- The luminous circle that had previously been fects which are more or less marked. In gen- constant was observed to alter immediately eral the lines are more numerous than in the from itself into an ellipse, and oscillate from spectra of flames containing the same saline right to left with a speed that enabled the new elements, which doubtless arises from the vibratory movement to be measured. This higher temperature, but in all cases the lines speed was faster or slower in proportion to the are the same as those given by Bunsen and increase or diminution of the number of eleKirchhoff. Thus with a saturated solution of ments used. Whenever the current was shut chloride of strontium, besides the orange and off, the normal state of the diapason returned, the clear blue, we see two violet rays, one more and the fixed luminous circle, due to its natuintense than the other, several green rays, one ral condition when vibrating, reappeared. M. of which is particularly distinct, and a certain Trèves conducted similar experiments upon number of feebler rays in different parts of the diapasons of soft iron, and of steel of various spectrum. Chloride of lithium, besides the red sizes, arriving at the similar results. M. Faye, and the feeble orange, gives a very vivid blue in a note to the French Academy, accompanyray. A concentrated solution of chloride of ing a report of the facts, says that the new excalcium gives a great number of rays, among perimental method of M. Trèves has made a which the dark-blue ray is very intense. Ohlo- marked step in the science of magnetism. ride of magnesium, besides other lines, gives two The Aurora Borealis as a Weather Prognosvery bright - green and one clear - blue ray. tic.-Mr. Murray Gladstone, of England, has Chloride of zinc gives a red ray, three brilliant for many years studied the aurora borealis as a blue rays, and a very intense violet line. Nic weather prognostic. He has observed that, trate of silver gives, among other rays, two of a when the coruscations are vivid, and particurivid green. In conclusion, the author points larly if they extend toward the zenith, or show out the very obvious and marked advantages much motion, they are almost invariably folwhich this method of observation offers in cer- lowed by a gale of wind with rain from S.W., tain cases over the usual method of ignition in within from forty-eight hours to four days. a non-luminous flame.

The more brilliant and lively the appearance The Electric Spark in a Vacuum.-MM. and motion of the aurora, the earlier the gale Alvergniat, Frères, have invented an apparatus which follows takes place, and the greater is to demonstrate that the electric spark cannot its severity. Slighter manifestations of the pass through a perfect vacuum. They create a northern lights are not followed by any apnearly absolute vacuum, by means of a mercu- preciable changes of weather. In explanation rial pneumatic machine, in the tube that serves of the connection between the two sets of phefor the experiment. This contains two plati- nomena, Mr. Gladstone suggests that when a nom wires, placed at a distance of two milli- larger body than usual of light air from the metres from each other. The tube is heated south begins to descend upon the cold stream to dull redness, and, when that point is attained, of air coming from the north, as those opposite the process of making the vacuum is still con- currents in the atmosphere come into close tinued, and the electric spark passed until it proximity, their negative and positive electriceases to be transmitted through the interior of cities produce coruscations. The rarity of the the tube The tube is then hermetically sealed atmosphere and the great elevation probably and separated from the machine. In a tube thus prevent (at least for the most part) any sound prepared, notwithstanding the slight distance or thunder being heard; and the former cause, between the two platinum points (two milli- joined with the manner in which the currents metres), electricity absolutely ceases to pass. approach each other, may probably occasion

Magnetism and Molecular Changes.-Exper- the shooting, flickering movements of the iments made by M. Trèves, a French naval

The arches of boreal light frequently officer, prove that a steel bar, magnetized by seen stretching from E. to W. may

be proan electric current, undergoes some molecular duced by large masses of air charged with change while magnetized. Two exactly iden- opposite electricities meeting each other and tical steel diapasons, giving sounds precisely in feeding the flames quietly and continuously, on unison, were selected. A small mirror was so an extended front; while the movements of placed in relation to each, that, when vibrations light occasionally occurring throughout the were struck upon either diapason, a figure of length of these arches may arise from the the vibrations was reflected into the mirror- masses of vapor coming more actively into


contact at particular points, and lighting up a drocyanic acid in affections of the stomach, of coruscation which, like a running fire, passes sulphate of copper, and of creosote. These, along the whole line. When the coruscations with his discoveries in the use of the stethoare more than usually vivid or violent in their scope, roused the opposition of his professional motion, it would indicate a larger arrival than brethren and brought a great deal of ridicule usual of negatively electric air from S. or S.W., upon him, without, however, affecting his repwhich, in a shorter or longer time, according utation, which was greatly increased by a to its strength, first checks, and then overpow- course of clinical lectures which he delivered ers the N. or N. E. wind, generally, blowing in London about that time. In 1831 he acwhen the aurora is seen. The lower tempera- cepted a professor's chair in the University ture of the atmosphere, cooled down by the College, and the course of lectures he delivered recent northerly wind, condenses the moisture immediately after was published at length borne from the warm south, and precipitates it The Lancet and The Medical Gazette. In 1837 in showers.

he turned his attention to the subject of animal Effects of Lightning. - General Morin has magnetism, and, having made a variety of er. communicated to the French Academy an illus- periments which satisfied him of its remedial tration of the heating effect of a flash of lightning, efficacy, he applied this mysterious agent to which penetrated a piece of furniture where the treatment of certain affections which were was placed a silk purse containing gold and sil- up to that time considered incurable. His ver pieces. The gold pieces were not fused, experiments excited public curiosity to the but slightly soldered together, without appar- highest pitch; but his new doctrine as to the ent alteration. The silver coins were com- curative powers of magnetism, while it made pletely defaced and strongly soldered together. many converts, raised up a host of adversaA more remarkable story was narrated to the ries against him, and he was ultimately comAcademy by M. Bobierre. It seems that at pelled to resign the professor's chair which he Nantes last July a violent storm occurred, and held. He was subsequently instrumental in a man on the bridge of the Canal de Bretagne establishing a hospital for the treatment of pafound himself, as he says, “enveloped in a tients on mesmeric principles, became the brilliant light.” Looking at the contents of founder of the Phrenological Society, of which his pocket-book some time after, he discov- he was elected president, and started, under ered that the silver pieces had a dull, partly- the title of The Zoist, a journal devoted to fused look; and on examining a gold piece in mesmerism and phrenology. Dr. Elliotson's another part of the pocket-book, separated best titles to fame are a remarkable work on from the silver by a partition of leather, he sulphate of quinine; his employment of creoobserved the gold piece uniformly covered by sote in excessive irritability of the stomach; a thin layer of silver, having the appearance his essay “on the Advantages of Sulphate of (under a microscope) of a multitude of globules Copper in Dysentery;" his discovery of the in contact with each other. A portion of this admirable curative properties and dioretic coating of silver having been removed by weak qualities of potash; his “Lectures on the Prinnitric acid, the gold below was found in the ciples and Practice of Medicine;" his translasame condition as the deposited silver, exhib- tion of Blumenbach's Institutiones Physiologiiting a slight appearance of fusion. M. Bo- , which passed through many editions, and bierre explained the phenomenon on the theory to which he had added more matter in the way that the electric shock, to which the man was of notes than the original work contained; and subjected when "enveloped in a brilliant his experiments in the use of the stethoscope, . light,” volatilized a portion of the silver, and Among his later works is one on “Surgical that the metallic vapor passed through the Cases in Mesmerism,” etc. leather, and coated the gold piece.

ELLIOTT, CHARLES LORING, one of the most ELLIOTSON, JOHN, M. D.; an English phy- distinguished of American portrait-painters, sician and medical professor and author, born born in Scipio, N. Y., in December, 1812; died in London in 1788; died in that city, July 29, in Albany, N. 'Y., August 25, 1868. His boy1868. He was educated at Jesus College, Cam- hood was passed in Syracuse, where his father bridge, and pursued his medical studies at was a builder. His father at first obtained a Guy's and St. Thomas's Hospital, and after- situation for him in a store, but, finding that ward at Edinburgh, where he took his medical he had no taste for mercantile pursuits, he dedegree, but subsequently became a Fellow of termined to make an architect of him ; but the Royal College of Physicians, London. He the boy's instincts for painting were too strong was appointed physician of St. Thomas's Hos- to be resisted. His friend F. S. Cozzens says pital, and assisted greatly in the establishment that “while a mere boy he narrowly escaped of a separate medical school there, in which he suffocation from locking himself up into his became a lecturer on state medicine, and after- bedroom, in order to paint 'The Burning of ward on the principles and practice of medi. Moscow,' during the winter, with no compancine. He distinguished himself also by the re- ion but a portable furnace of burning charcoal form of several administrative abuses in the to keep himself warm. In after-days, at the hospital, as well as by the adoption of some early age of fourteen, he made a copy of the new prescriptions, among them those of by- portrait of a clergyman, which he painted with three colors only—black, white, and rose pink. reēlected the three following years. He twice This portrait is in the possession of his family, declined, during the period of his service as and shows that even at an early age the artist Governor, an election to the United States had acquired a delicate sense of art in the ar- Senate—from an unwillingness to be further rangement of the drapery, the tenderness of drawn away from his cherished profession. In the expression of the mouth, the modelling, 1847 he was elected by the Legislature a judge and the freedom of touch in the painting of of the Superior Court, and of the Supreme the hair, some of which characteristics are ap- Court of Errors, and remained on the bench as parent in his latest pictures.” Finding that one of the associate judges of the Supreme his passion for art was so strong, his father Court, until he reached the age of seventy, wisely allowed him to pursue the necessary when his term expired by limitation of law. studies to become a painter. Having learned He then retired to private life, carrying with what he could of his art, and become a very him, however, the unabated interest in public fair portrait-painter in Syracuse, he came to affairs, and in religious and charitable enterNew York in 1833, or the beginning of 1834, prises, which made his life so honored and useand became a pupil of Trumbull

, and subse- ful to the last. Since 1827 he had held the quently of Quidor, a fancy painter of some appointment of Professor of Law in Trinity note. While here, he painted portraits of College. He received the degree of LL. D. Captain and Mrs. Cornelius Vanderbilt, for from the University of New York in 1838. which he received the modest sum of fifty dol- ENGLE, Rear-Admiral FREDERICK, U. S. N., lars each. He also painted in oils some scenes A distinguished officer of the Navy, born in from Irving's and Paulding's works, which Delaware County, Pa., in 1799; died in Philwere thought very creditable for so young an adelphia, February 12, 1868. He entered the artist. After a residence of little more than service November 30, 1814, and had consea year in New York City, he returned to West- quently been a naval officer for more than ern New York and practised his profession, fifty-three years, of which almost twenty had confining himself particularly to portrait-paint- been passed afloat. At the beginning of the ing, for about ten years. He returned to New Mexican War he had risen to the rank of York City in 1845, and in 1846 became a captain, and commanded the Princeton, winmember of the National Academy of Design. ning distinction by his services in the blockadFrom that time he had been a resident of New ing squadron. When treason threatened the York or its immediate neighborhood, though capture of the United States Navy, Captain occasionally absent for several months at Al- Engle, as an officer worthy of confidence, was bany or Washington. He had painted a large sent to China to assumo command of the number of portraits, and all were remarkable Hartford, and brought that powerful ship for the fidelity of their likeness, the vigor and home to aid in overcoming the South. His perfection of their coloring, and for presenting advanced age disabled him; he was therethe sitter in his most characteristic and effec- fore assigned to the command of the Navytive expression. In private life he was one of Yard at Philadelphia, and subsequently became the most genial and social of men.

Governor of the Naval Asylum in that city. ELLSWORTH, WILLIAM WOLOOTT, LL. D., He was promoted to be rear admiral on the an eminent Connecticut jurist, born in Wind- retired list, July 25, 1866. Finally, after a sor, Conn., November 10, 1791 ; died at Hart- long life of honorable service to his country, ford, Conn., January 15, 1868,' He was the he resigned his office, and remained thencethird son of Oliver Ellsworth, second Chief forward waiting orders, until his death. Justice of the United States, and a twin brother EUROPE. The aspect of Europe during the of the late Henry L. Ellsworth, long Commis- year 1868 was, on the whole, of a pacific sioner of Patents at Washington, D. O. He character. The great powers seemed desirous graduated from Yale College in the class of to preserve peace, and none of the important 1810, and at once commenced his legal studies international questions—the German, the Rounder Judges Reeve and Gould in the Law man, and the Eastern-brought on a war. School at Litchfield, and afterward continued There was, however, one serious breach of them in Hartford, in the office of his brother- the universal peace the revolution in Spain. in-law, the late Chief-Justice Williams. He Being unconnected with any of the great inwas admitted to the bar in 1813, and was en- ternational complications which have agitated gaged in the successful practice of his profes- Europe for years, its effects did not extend besion until 1829, when he was elected to Con- yond the change of the form of government gress and twice reëlected at the expiration of in Spain. It occupies a remarkable place in his term. He resigned, however, at the close the history of European revolutions for the of the first session of the Twenty-third Con- rapidity with which it spread, and the univergress, to return to his profession. He was & sal support it met with. Within a few weeks member of the Judiciary Committee during the after the raising of the first insurrectionary whole of this period, and a member of the cry, in September, it overthrew the throne of committee appointed to investigate the affairs Queen Isabella, For the remainder of the of the United States Bank at Philadelphia. In year Spain was administered by a Provisional 1838 he was chosen Governor of the State, and Government, which represented three parties,

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