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county of Cumberland. The pre- our readers; and we subjoin at sent is not the proper occasion for the same time one answer, though entering into its history, as it is, we cannot say that this method is properly speaking, a compound,and an easy one. However, we have no as such will be hereafter described, doubt that some of our CorrespondIt is a well-known substance, and ents will be able to give our inis largely employed in the arts, sup- quiring friend more information. plying us both with crucibles and “The Editor of the Chemist will pencils : it is now mentioned from much oblige a subscriber and sinits being almost wholly composed cere well-wisher, if he or any of of carbon, and from some late ex- his Correspondents can point out perimenters having succeeded in an easy mode of restoring rancid forming crystals as hard as dia- butter, so as to render it fit for monds, by exposing it to strong use. fusion. Black lead, which is a “ April 14, 1824.” very improper name, is, in fact, a Melt the butter over a slow fire, carburetor iron, and contains about or by means of a water-bath, at a 91 parts carbon, and 9 iron. When heat not exceeding. 180° Fahr., burnt with dry oxygen gas, mois and remove the scum as it arises. ture was deposited, which shows Continue the operation till all the that, like charcoal, it contains hy matter that will subside to the botdrogen. This substance was lately tom has done so, and the butter is fused by the blow-pipe, and the re- transparent. Then decant it or sult was numerous globules of strain it through a cloth, and cool matter having a high vitreous it in a mixture of pounded ice and lustre, and considerable beauty. salt, or in cold spring water, otherSome of thein were of jet black, wise it will become lumpy. When like the most perfect obsidian; cool, it will not have entirely lost others were brown, yellow, and to

its rancidity, but it will be much paz coloured; others were greyish

improved. If afterwards well washwhite, like pearls, with the trans- ed with pure water or with ardent parency and lustre of porcelain; spirits, or, still better, with a small and others were limpid like flint quantity of sweet milk, its taste glass, or, in some cases, like the will be found much, if not wholly opal. They were so hard as to corrected. scratch flint glass, window glass, GALLIC ACID CONVERTED and the hard green variety out of

INTO ULMIN. which aquafortis bottles are made, ULMIN is a curious substance, Some of the globules were scarcely exuding from some trees, and reto be distinguished by the eye from sembling guin, in some respects, diamonds. We have, therefore, but is not like it, sticky and capain this experiment on the soft and ble of being formed into a paste, greasy substance, black lead, as in Gallic acid is also a vegetable subSir Humphrey Davy's experiment stance, found in the parts of many before mentioned, on charcoal, a plants, but more particularly in proof of the great chemical simi- nut-galls, from which it is named. larity between diamonds, plum, Professor Döbereiner lately found, bago, and charcoal; but we have on dissolving a determinate quanalso in the other experiments and tity of gallic acid in ammonia, and results which have been mentioned, placing the solution in contact with a decisive proof that they are not oxygen, that it absorbed sufficient precisely the same, for both plum- to convert all the hydrogen of the bago and charcoal are combined gallic acid into water. By this with hydrogen,

abstraction the gallic acid became

converted into ulmin, which, the TO MAKE RANCID BUTTER Professor says, may be representFRESH.

ed as a combination of two volumes We beg leave to recommend the of gaseous oxide of carbon, and one following request to the notice of volume of vapour of water.

ILLUSTRATION OF THE PRIN. and to the conviction then gaining

CIPLE OF THE SAFETY ground, that to hunt after the phiLAMP.

losopher's stone was philosophic Take a single thread of cotton, folly, was falling into disrepute, immerso it in oil, and allow it to there was a danger that the nuburn, by means of a cork float, im

merous discoveries made by the mediately on the surface of the oil. alchymists, and the facts known to The flame will be about one-thir- them, should be forgotten or lost tieth of an inch in diameter. Take to the world for ever. The bad a fine iron wire, about one hundred character of the professors had exand an eightieth of an inch in dia- tended itself to every thing conmeter, form it into a ring of a tenth nected with them; and rational of an inch in diameter, and place persons, despising their tricks, it over the flame. Though there is were disposed to reject even their a considerable space between the knowledge. At that time there flame and the ring, if the latter be arose a man, thoroughly acquaintcold the former will be instantly ed with all the facts which had extinguished; but if it be held been discovered by the alchymists, above the flame, so as to be slightly capable of arranging them, and heated, it may be passed over the who, at the same time, knew some flame without extinguishing it. of the important purposes to which This depends on the power of the they might be applied. This man metal to abstract the heat of the was John Joachim Beccher, who flame. Sir H. Davy employed a seems to have been of Jewish exglass ring of the same diameter traction, and was born at Spiers, and size as the iron ring, which, in the year 1625. He was first a being a bad conductor of heat, did professor of medicine; then phy. not extinguish the flame even when sician to the Elector of Mentz; and cold : but when a thicker glass was afterwards 'lived at the court of employed, and the ring made of a Bavaria in the same capacity. smaller cireumference, it acted like Towards the close of his life, he the iron wire, and extinguished the came over to England, and died at flame, unless heated. Again, if a London about 1682, it is supposed, small globe of metal, one-twentieth in great poverty. This man is conof an inch in diameter, made by sidered to have collected, from fusing the end of a wire, be brought amidst the rubbish and gems of the near the flame of a single thread alchymists, the materials for the of cotton, such as above described, foundation of the present science it will, when cold, extinguish it at of chemistry. In a work which he the distance of its own diameter. published at Frankfort, in GerLet it be heated, and the distance many, in the year 1669, entitled, at which it operates will be dimi- Physica Subterranea, he pointed out nished in proportion. These expe- the use which might be made of riments show that small metallic the discoveries of the alchymists, apertures, which admit both light and the proper objects to which the and air, will extinguish flame; researches of chemists ought to be and on this principle Sir H. Davy directed. The publication of his surrounds the miner's candle with work forms a very important era a case of inetallic gauze, and the in the history of chemistry; and flame is prevented, even when in chemists having since then purcontact with an inflammable gas, sued the path which he indicated, from proceeding beyond the gauze. have brought the science to its

present state. Perhaps the world BIOGRAPHICAL NOTICE OF may regret that so little is known

BECCHER, AN EMINENT of this celebrated chemist : but CHEMIST.

the fame of Beccher, like that of In the middle of the 17th century, most of the early improvers of when alchymy, owing to the nu- science, rests entirely on the single merous tricks of the alchymists, work which bears his name.

in the state of filings or pails, is to be added in a quantity which ought previously to be determined, and the whole dissolved in boiling nitro-muriatic acid, so much nitric acid being used that no protoxide of iron remain in the solution; evaporate to dryness and re-dis

solve in water, when a large quanTHE ELECTROPHOROUS OF tity of arseniate of iron will be left. VOLTA.

Add to the solutions successive (In answer to a. Correspondent.) portions of carbonate of soda until A CORRESPONDENT, some time ago, a greenish precipitate appears, at requested to be informed of the best which time all the arsenic and iron manner of making an electropho- will be separated, and part of the rous. We are not aware that any copper; the rest of the copper may other or better method has been be separated by sulphuretted hydiscovered than that of the in- drogen, and the clear solution thus ventor of the instrument, the cele obtained, when boiled with subbrated Volta. Our Plate repre- carbonate of soda, yields the carsents the form of his electrophorous. bonate of nickel.

: A is a circular plate of metal, or Thus obtained, the carbonate of piece of wood, covered with tin: nickcl contains a little.cobalt; to foil, which has a glass handle, F, separate the latter, the precipitate, screwed into a brass or wooden as obtained above, by boiling with nut, D. The edge of this plate

sub-carbonate of soda, is to be must be pretty thick, and well well wasbed, and diffused whilst smoothed and rounded off. The moist in water, and a current of Tower plate. B.: consists of a re- chlorine passed into it until in exsinous cake, and another metallic cess: the excess of chlorine is to plate. The resinous cake is form

be allowed to dissipate, and the ed by melting together equal parts solution filtered; it now contains of shell lac, resin and Venice tur- not the smallest trace of cobalt, pentine; and it may either be pour- that remaining as a hydrated pered, when fluid, on the metallic oxide, with a certain portion of: plate, if it be provided with a rim, nickel in the same state. If in the or it may be poured on a marble

mixed carbonate of nickel and coslab, from which it can be easily

balt, the latter is in excess, the separated, when cold, and applied residue, after the action of the to the metal. Of the three plates. chlorine, is pure hydrate of cobalt, A is called the upper conductor; B and the solution contains the nickel the resinous plate; and C the lower with a small quantity of cobalt.conductor. We presume our Cor- Ann. de Chim. xxv. 95. respondent does not require us to describe the uses of this instru

NEW PYROPHORUS: OR. ment; and that he knows it is an

. INSTANTANEOUS FIRE

i electrical machine, about 20 sparks

LIGHTER. from the upper conductor being

In determining the composition of sufficient to charge a small Leyden

tartrate of lead, Dr. Friedman Gophial.

bel, of Jena, observed that this

salt, when heated in a glass tube, ECONOMICAL PREPARATION formed a fine pyrophorus. When OF PURE OXIDE OF NICKEL. a portion of the deep brown mass

Speiss, or impure nickel, is to is projected from the tube, it inbe reduced to fine powder, and stantly . takes fire, and brilliant roasted till it gives off no further globules of metallic lead appear on vapours of arsenic, the heat being the surface of the substance in igat first moderate, to prevent fusion, nition. The effect continues much and then increased. Metallic iron, longer than in other pyrophori.

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WATER-SPOUTS. at rest. If you think them worthy To the Editor of The Chemist. of insertion in your Journal, you SIR, -Among the meteorological will gratify a constant reader, and phenomena which have long ex- an

OLD SAILOR. cited the attention and inquiries Your readers doubtless know, of pbilosophers, none seems in-' that water-spouts are dark black volved in more darkness and ob. clouds, of a funnel kind of shape, scurity than that of water-spouts. which descend from above to the As your Journal is devoted to sea, and which are supposed to scientific subjects, and as this as convey water into the atmosphere. well as most other meteorological The drawing I send represents phenomena, fall within the depart- them as they generally occur. At ment of Chemistry, and can only their first formation, they appear, be explained by chemical princi- according to Capt. Maxwell's acples, I trust you will allow me to count, as at a, where the black present your readers with a dc- cloud drops from a level surface scription of these phenomena, and into a conical form before the disafterwards to offer a few words in turbance at the surface of the sea, explanation.

as shown at D, is observed. The A full explanation I hold to be effect produced at D is like that of impossible, till it is clearly ascer- a smoking furnace. The black tained what are the changes which conical cloud now continues to dewater undergoes when taken into scend, as shown at B, till it almost the atmosphere; how it is disposed reaches the surface of the sea, and of when there; and what occasions the smoke-like appearance rises it afterwards to form and fall. higher and higher, till it forms a Your readers, acquainted with me- union with the cloud, from which teorology, well know that these are the spout appears to be suspended. doubtful points, which science has In this situation it is said to put on not yet fully investigated. My ob- its most terrific appearanee to the servations will rather tend to put mariners who have the misfortune other persons in the right path of to be in its neighbourhood. When inquiry, than to set the question the spout begins to disperse, it as

sumes the appearance shown at C. affected by the variable wind, which The black cloud generally draws then preyailed from all points of itself up in a ragged form, but the compass. It next retarned to leaves a thin transparent tube, the northward, in direct opposition CE, which reaches to the water, to the prevailing wind, and right where the smoke-like commotion upon the ship's starboard beam, still prevails. At this time there whose course was altered to east, is a curious motion in the upper in hopes of letting it pass a-stern. part of the tube. .

Its approach, however, was so raAnother witness says, it was ob- pid, that we were obliged to resort servable of all of them, but chiefly to the usual expedient of a broad. of the large pillar, that, towards the side, for the purpose of averting end, it began to appear like a hol- the danger; when, after firing selow canal, only black in the bor- veral shots, and one in particular ders, but white in the middle; and having passed right through it, it though at first it was altogether appeared for a minute as if cut black and opaque, yet one could horizontally in two parts, the divivery distinctly perceive the sea- sions waving to and fro in different water to fly up along the middle of this directions, as if agitated by oppo-canal, as smoke does up a chimney, and site winds, till they again joined that with great swiftness and very per, for a time, and at last dissipated ceptible motion; and then soon after in an immense dark cloud or shower of the spout or canal burst in the mid- rain. The near edge showered in dle, and disappeared, by little and large heavy drops on the ship's deck, little, the boiling up and the pillar- till the cloud was quite exhausted. At like form of the sea water continuing the time of firing the gun, its base always the last, even for some con- covered a portion of the surface of siderable time after the spout dis- the water, equal to half a furlong, appeared, and perhaps till the or 300 feet in diameter, while the spout appeared again, or reformed cloud itself extended over head and itself, which it commonly did at the all round to a very considerable same place as before, breaking and distance. There was never much forming itself again several times wind,Capt. Napier adds; " and in a quarter of an hour.

the water that fell from the cloud Captain Napier thus describes and was caught in the foot of the one which he saw, on Sept. 6th, driver (a sail) was perfectly fresh. 1814, in lat. 30° 47' N., and long. Low heavy black clouds were 62° 40' W.;-—" The wind being hanging about, occasional drops of variable, between N. N.W, and rain followed, the mercury in the N.N.E., the ship steering S.E., an barometer became considerably extraordinary sort of whirlwind more convex, and was followed by a was observed to form, about three clear atmosphere and hot sultry weacables' length from the starboard ther." bow of his Majesty's ship Erne, It

(To be continued.) carried the water up along with it in a cylindrical form, in diameter, LECTURES ON CHEMISTRY, to appearance, like that of a water

AT THE MECHANICS' INbutt, gradually rising in height, in- STITUTION. creasing in bulk, and advancing It was impossible for us in in a southerly direction. At the our last Number to do any thing distance of a mile from the ship it more than merely notice Mr. Philcontinued stationary for several lips's first Lecture; and we were, minutes, boiling and foaming at therefore, obliged to postpone to the base, discharging an immense co a better opportunity laying an outlumin of water, with a rushing or hissing line of it before our readers. Mr. noise, into the overhanging clouds, Phillips began by bespeaking the turning itself with a quick spiral attention of his hearers, making motion, constantly bending and an apology for using some terms straightening, according as it was which might probably be unknown

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