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quiet. There was no boisterousness, no to the prepared surface of a particular indecorum, no extravagant merriment, kind of stone, and by subsequent prono loud laughter, much less those con- cesses, it is possible to obtain a number. tentions, and babblings, and wounds of such figures on paper; and so, by the without cause, which are the invariable deposition of metal by electricity, a accompaniments of our more civilized similar multiplication is effected. As festivities. The reason of the difference therefore the one art is called lithograis to be found in the habitual moderation phy, the other may be termed electroand self-command of Turks, and in the graphy: absence among them of the grand source But little alteration has been made in of the woe and sorrow which generally the process of taking copies of engraved follow our
seasons of hilarity. plates. There are two methods : one is Special care is exercised by the Turkish to submit the plate, which is to be authorities during Bairam to keep Mus- copied, to the action of the electricity in sulmans from the grog shops, which, a suitable apparatus, and to form I am sorry to add, are chiefly tenanted mould by depositing the copper on it in by Christians. The only part of the the manner already described in the population which give free vent to their Visitor. The other method is to form mirth are the boys. You may see them a mould of lead, by pressing the enriding double on donkeys, racing on graved plate and the plate of lead tohorses, or turning on swings, of which gether in a strong press, and then dethere are at least four kinds in use at positing copper upon it in the usual way. Constantinople. You may see them The latter process is most readily perplaying and tumbling in the courts of formed; but the experimenter must be the mosques, firing crackers and eating careful that the lead is perfectly clean. sweetmeats, as New England boys do It will be found of advantage to plane on the fourth of July. By some, certain the metal before it is used, which may hours of the festival are devoted to more be easily done with the tool called by serious purposes:
The bereaved visit carpenters a jack plane. the graves of friends, and sit by them The method of separating the electroand turn up the sod throughout, as if graphic plate from that on which it has the sight of the new earth brought into been deposited, as recommended by Mr. fresh recollection the hour when the Spencer, is exceedingly ingenious, and loved ones that repose beneath were will be found, in most cases, sufficient, shut from their eyes.- Southgate. if the precautions mentioned in the
Visitor have been attended to. The
plate on which the deposit is formed, IMPROVEMENTS IN ELECTROGRAPHY. should be held over a spirit lamp, if of
In the Visitor for 1840, pp. 187. small dimensions, or otherwise over a 273, a description was given of Mr. charcoal fire; and when it has been Spencer's newly-discovered process of raised to a temperature of about three taking impressions of coins, medals, and hundred degrees Fahrenheit, cold water engravings, by the agency of voltaic should be poured on the deposited plate, electricity. During the past year this which causes a sudden contraction, and gentleman has been engaged in bringing consequently loosens its contact with the his invention to a more perfect state, mould. It will also be found of advanand in extending its applications. The tage to produce á vibration in the mould, results of his labours we shall attempt to by striking it with some metallic subexplain, in a popular manner, for the stance. When the plates are separated benefit of our readers. The art has been at the edges, a small wedge may be named by some of its admirers, electro- inserted, which will facilitate the distype ; but it has been termed, with more union. propriety, electrography by Mr. Spencer To obtain facsimiles of medals and himself. This term seems to us exceed- coins, the impressions of both sides may ingly appropriate, as conveying a notion be taken on lead, which are employed, of its resemblance, in its general pur- in the voltaic process, by the same arposes, to lithography, zincography, and rangement as engraved plates. Another other arts in which the representations method of obtaining a suitable mould, is of objects, on prepared surfaces, are to cast the coin in Newton's fusible transferred for the purpose of multiplica- metal, which is a compound of three tion. By the transference of a drawing parts of tin, five of lead, and eight of bismuth, and is reduced to a liquid state chloride, by a process similar to that at so low a temperature, that it is melted adopted for copper ; but with all the care in boiling water. This substance, how- that can be used, and employing weak ever, is liable to crystallize in cooling, and pure solutions, which are found to which must injure the sharpness of the succeed best, the effects are not such as casting, and on this account an amalgam are desired. The experiment frequently called “Smith's solder for tin” will be requires to be repeated several times; preferable. Still more recently it has and then the coating is so exceedingly been discovered, that plaster moulds thin, that it may be removed by the may be used, provided they are pre- friction of the finger. It might, howviously prepared with plumbago, for a ever, be supposed an easy matter to cormetallic surface is thus presented, and rect this disadvantage, by continuing the the deposition goes on as rapidly as operation until a sufficiently thick coatif a solid mass of metal were em- | ing of the metal was obtained; but it is ployed.
found, by experiment, that gold cannot T'he deposition of solid voltaic plates be deposited on gold. 66 Whenever the having the lines in relief, is easily effected silver or copper, says Mr. Spencer, by the process employed by Mr. Spencer “ becomes completely covered with a in his first experiments; but it has not thin film of gold, it ceases to be silver or proved very useful to the printer, as the copper, as respects the surrounding solines are thick and coarse. It might, lution, or its electrical properties; and however, be employed to take impres- no more than this one coating can be de. sions of geometrical figures, in which a posited in the solid state, by any, electrical strength of line is desirable, and the process as yet discovered. It will, under plates might then be introduced with the these circumstances, at once be obvious, type, and printed from in the same man- that the coating must be chemically thin. ner as wood blocks. Another method of Were we able, by this process, to deposit forming this kind of voltaic plate, has a second coat, there would be nothing to since been recommended by the same prevent a third, and so on; in that case author, as one which will probably be flowers of gold, or other ornaments in found useful in the hands of the practical relief, might be deposited on silver, or engraver. “ Take a copper or brass vice versa. I have been, however, more plate, and give it a coating of fine plas- successful with silver under certain moter of paris, or other substance. When difications." dry, let the surface of the plaster be M. de la Rive, a foreign philosopher rubbed down level, until there is as of great celebrity and genius, has promuch thickness left as the lines are re- posed a method of gilding, by a similar quired to be in relief to print from. It process to that already mentioned; but must now be smoked with the flame of a it offers no advantages over the mode lamp, and the lines drawn on the surface now in common use. The experiments thus prepared. The brass or copper- with platinum have been even more plate will prevent the point used from unsuccessful; for although it may be degoing deeper than is necessary, conse- posited from its chloride, in the same quently the lines will be all of the same manner as gold, it appears in the form of depth. When the engraving is com- a brittle black powder, “at present afpleted, let the plaster surface be metal- fording small hope of usefulness.” ized, a process which will be explained During the past year, many attempts presently. A solid plate of copper may have been made to form electrographs of then be deposited on it, and all the raised other metals than copper and silver, parts will be perfectly level. These are and some persons, having either deceived ihe principal improvements made in the themselves, or wishing to deceive others, process of taking impressions in copper have asserted, that they had succeeded in from metallic plates, and no further so doing. Upon a repetition of their exconsiderable alteration will probably be periments, the fraud has been detected. made until the art comes into the hands At the very commencement of this imof practical men.”
portant art, an attempt of this kind was Attempts have been made to deposit made, and it has been so continued, that gold, silver, platinum, and other metals, it is necessary to caution the reader in the same manner as copper; but these against these disgraceful impositions, and have been but partially successful. Gold to recommend a repetition of the premay be precipitated from the state of a | tended experiments.
The process of electrography cannot size, may be thus metallized with equal be effected except on a metallic surface; facility." and it has therefore been an important By the discovery of this ingenious consideration, what means could be mode of manipulation, the application of adopted to give such a surface to plaster, the electrograph (a term applied by Mr. wooden, or clay moulds. The method Spencer to the instrument employed in first employed was, that of covering them the depositions) is greatly extended. with gold leaf ; but this was not only a Had it been confined to the multiplicaclumsy process, but one which injured tion of works of art, from copper or the sharpness of the model, and conse- even from metals generally, it would quently made the electric copy much in- have been too limited in its use to meet ferior to the original. Mr. Spencer has the wants of manufacturers in the present since discovered another process, which day. But now every substance may be is an extremely pretty chemical experi- fitted to receive the deposition of copper, ment, altogether independent of its use and consequently may be multiplied in this art, and one which will probably without end. It is thus by the slow and be found useful for many other purposes. persevering efforts of ingenious, if not The description given by the discoverer of great minds, that the limits of human is so simple, that it will be better to knowledge are widened ; improvements adopt his own words, than attempt a are made in the arts, which administer more familiar explanation. Suppose to our mental enjoyments, or bodily it to be an engraved wooden block which comforts, and a clearer view is obtained you are desirous of metallizing, in order of the arrangements of physical existthat copper may be deposited on its sur- ence, and the union or unity of natural face; this example holding good for any other material. The first operation is to The importance of this wonderful art take strong alcohol, or spirits of turpen- is now beginning to be known. To the tine, in a glass vessel, and add to it a engraver it is useful, because it enables piece of phosphorus ; a common phial him to multiply the number of his plates, corked will answer the purpose: the
so that when one has been engraven, vessel must now be placed in hot water hundreds may be made from it. Nor for a minutes, and occasionally are the copies in any degree inferior to shaken. By this means the alcohol will the original, for each will have not only take up about a three hundredth of its the sharpness, but also the same burbulk of phosphorus, and we thus obtain nished appearance of the surface, so that a solution of phosphorus. Next procure one cannot be distinguished from the a wcak solution of nitrate of silver, place other. To the type founder it is also of it in a flat dish or saucer; the engraved great value, for it enables him to proface of the block must now be dipped in vide, without difficulty, a copper matrix, this solution, and let remain for a few and at a trifling cost. The calico printer seconds, to allow capillary action to draw has already availed himself of its assistthe nitrate of silver into the wood. ance; and to the potter it is hardly less "This operation being performed, a valuable. These, however, are but a
, small portion of the solution of phospho- few of the purposes for which it will be rus must be poured in a capsule, or watch found applicable.
H. glass, and this be placed on a sand bath,* that it may gradually evaporate. The block must now be held with its surface
GENTLE REPROOFS.-No. III. over the vapour, and an immediate change takes place; the nitrate of silver be- In passing through Hackney charchcomes deoxidized, and gives place to yard, I observed two boys amusing metallic silver, which allows the vol- themselves in throwing stones at a newlytaic deposit to go on with as much erected tombstone, Every time they rapidity and certainty as the purest succeeded in striking it, a shout of trisilver or copper.
The whole process umph announced their satisfaction. It may be performed in a few minutes, and seemed not to occur to them, that, by with absolute certainty of success. The chipping the stone, and defacing the ininterior or exterior surface of a plaster or scription thereon, they might be the clay mould of a statue, no matter what means of wounding the feelings of the *** A little hot sand in a saucer will answer the
surviving relatives of him who lay slum.. purpose.-ED.
bering in the ground. It was but a boy
ACCIDENT AT THE FALLS OF NIAGARA.
ish frolic, but still it required correction; mer, he raises one cover after another, for few of us would like to see the erected and insists on finding out what these memorial of those we love wantonly in- unknown dishes are composed of. In jured and obliterated.
spite of all the advice of the charitable The boys had nothing vulgar about man to partake first of the more subthem, and judging by their dress and stantial dishes, he dwells with obstinate general deportment, I doubted not they inquiry on nicer compounds, until overwere the sons of gentlemen residing in come with exhaustion, he drops down. the neighbourhood. Walking quietly What do you think of such a man ?" among the graves, I soon came to the “ He is a fool,” said the convict, “and place where they stood. “Young gen- I will be one no longer. I understand tleman !" said I, mildly to the eldest of you well.”--Dr. Leiber's Essay on them, “if that were your father's tomb- | Penal Law. stone, should you like to see me throwing stones at it ?" He looked surprised, and after a little hesitation, said, “No, sir.” “Then,” said I, “though it is not THERE are so many instances wherein your father's, how do you know that it the daring actions of bold men are held is not mine ?” With somewhat of con- up to public admiration, though the mofusion in his face, he dropped the stone tive that occasioned them was any thing he had in his hand, and walked, with but commendable, that it becomes a kind his companion, to the churchyard gate. of duty to give publicity to acts of a Much more gladly would I have sent him similar kind, when the desire that inaway with a happy heart, than with a spires them is creditable to humanity. clouded brow; but perhaps it was best The bravery manifested in defending the as it was : for when next he passes the oppressed, in protecting the property of tombstone, my reproof may again rise another, and in rescuing those who are up in his remembrance, and prevent the in danger from destruction, is entitled to recurrence of such thoughtless indis- the homage of mankind. An instance cretion.
of this latter description is as follows. According to the “Buffalo Commercial Advertiser,” an occurrence of the most
thrilling interest took place at Niagara A GENTLEMAN who visits with great Falls, attended with imminent peril to the regularity the Philadelphia Penitentiary, lives of two individuals, but resulting in the inmates of which his piety prompts a most happy and providential deliverhim to instruct, had given a Bible to ance. The new bridge to Iris Island, is a convict, who would ask him, at each planted in a frightful rapid, where the visit, with much shrewdness, some dif- current is from twenty to thirty miles an ficult question formed from passages hour, and is only about one hundred, or of the sacred volume ; each time de- one hundred and fifty yards above the brow claring he would not go on, if this was of the great precipice or perpendicular not first explained to him. The gen. fall. A carpenter, of the name of Chatleman was unable to persuade him that pin, was engaged with others in covering it would be best for him first to dwell the bridge, and while at work upon the upon those passages which he could staging, about one hundred feet from easily understand, and which plainly Iris Island, accidentally lost his footing, applied to his situation. After many and was precipitated into the rapids, and fruitless trials to induce the convict to in the twinkling of an eye swept away this course, his friendly teacher said, toward the great cataract. Speedy and “What would you think of a very inevitable destruction seemed to await hungry man, who had not eaten å him; but, happily, he was uninjured by morsel of food for the last twenty-four the fall, and even in this most helpless hours, and was asked by a charitable condition, retained perfect self-possesman to come in and sit down at a richly sion. Turning his eye toward the only covered table, on which were large point of hope above the fearful precipice, dishes of choice meat, and also covered he succeeded, by great dexterity in swimones, the contents of which the hungry ming, in effecting a landing upon a little man did not know. Instead of satis- island some twenty feet in width and fying his exhausted body with the for- length, the outermost of a group of little
OBSCURE PASSAGES IN THE BIBLE.
cedar islands, situated some thirty or interest of the whole scene was heightenforty yards above the falls, and about ed by the presence of Chapin's wife and equi-distant from Goat Island and the children, who stood on the shore, watchAmerican shore. There he stood for an ing with unavailing horror and agony hour, looking beseechingly back upon what seemed his inevitable fate. Let us the numerous spectators who lined the hope that they called this to mind, as a bridge and shores, but with whom he stimulus to that sincere and grateful could hold no conversation, on account praise which was due to God. Apart of the distance and the roar of the rapids. from His interposition, there would have There is a man in the village of the falls, been no instrument at hand, or had there of the name of Robinson, of extraordi- been one, he would have toiled in vain. nary muscular power, great intrepidity,
G. and withal an admirable boatman, and he was probably the only one that could have been found within fifty miles, who gene
The treasures of wisdom and knowrously volunteered his services, to at ledge, which are amassed in the five tempt reaching the island in a boat, and books of Moses, have enriched the whole bring Chapin off. A light boat of two civilized earth, and, indeed, greatly prooars was soon procured, and he em- moted that very civilization. They have barked. He proceeded with great deli- been a kind of text book to almost every beration and consummate skill, darting writer on geology, geography, chronhis little boat across the rapid channels, ology, astronomy, natural history, ethics, and at the intervening eddies holding up jurisprudence, political economy, theto survey his situation, and recruit his ology, poetry, and criticism, from the strength for the next trial. In a few time of Moses to the present day. Books minutes, he neared the island, but a rapid to which the choicest writers and phichannel still intervened, sweeping close losophers in Pagan antiquity have been to the island, and rendering the attempt deeply indebted, and which were the to land very difficult. He paused for a text-books to all the prophets ; books moment, and then, with all his strength, from which the flimsy writers against darted across and sprang from his boat; Divine revelation, have derived their his foot slipped, and he fell backward natural religion, and all their moral ex. into the rapid current; with the specta- cellence; books written in all the energy tors it was a moment of thrilling interest and purity of the incomparable language and breathless silence; his boat seemed in which they are composed; and, lastly, inevitably lost, and himself in fearful books which, for importance of matter, jeopardy: Retaining, however his grasp variety of information, dignity of sention the boat, he sprang in, and again ment, accuracy of facts, impartiality, seizing his oars, brought up under the simplicity, and sublimity of narration, lee of the little island. All again felt a tending to improve and ennoble the momentary relief; but still the great intellect, and ameliorate the physical and labour and hazard of the enterprise re
moral condition of man, have never been mained to be overcome. A cool head equalled, and can only be paralleled by and a strong arm only could effect it. the gospel of the Son of God! FounRobinson proved equal to the task. tain of endless mercy, justice, truth, and Taking his companion on board, in the beneficence ! how much are thy gifts same careful and deliberate manner, and beauties neglected by those who do though at infinitely greater hazard and not read this law; and by those who labour, they effected a safe landing on having read it, are not morally improved Goat Island. There the spectators as- by it and made wise unto salvation !sembled to give them a cordial greeting. Dr. A. Clarke. A scene of great excitement ensued; the boat was drawn up the bank, and it was moved, and carried by acclamation, that The true spirit of religion cheers as a collection be made upon the spot for well as composes the mind; it banishes Chapin and his deliverer, Robinson. indeed all levity of behaviour and dis
After the collection, Robinson and solute mirth; but fills the mind with Chapin took their seats in the boat, and perpetual serenity, uninterrupted cheerwere carried in triumph on the shoulders fulness, and an habitual inclination to of their neighbours to the village. The please others, and be pleased ourselves.