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surer to the government of Stora deprived of the honour of having Kopporberg. He went to school discovered this process, it was at at Westeras, and was afterwards first made known' to the world by sent to the University of Upsala. the works of Bergman. He next His mind was early turned to sci. taught philosophers the scientific entific pursuits, with a zeal which value of the blow-pipe, which, beat once carried him rapidly for- fore his time, was only used by ward, and made him study deeply workmen, and drew up a conas he went. While yet in the aca- cise summary of directions for demy, he dropped a specimen of its use, which were published in crystallized carbonate of lime, and Berzelius's Elements of Chemistry. the fall shattered it into fragments. He was also the inventor of a baBy this accident the original nu. lance, remarkable both for its excleus of the crystal was developed, treme delicacy and the simplicity and Gahn, pursuing the idea which of the plan on which it is conthis suggested, and which would structed, so that it can be made by bave been lost for any other per- any ordinary workman. In all son, succeeded, by cleavage, in these cases Gahn seems to have extracting the rhomboid, which been so indifferent to celebrity, as constitutes the primitive form of to have made no effort to claim this mineral, from a great variety what was fairly his due. The auof secondary crystals. Bergman, thor of the biographical memoir to whom this observation and dis- which we are now abridging, ascovery were conimunicated, pub- cribes his unwillingness to come Jished, immediately afterwards, a before the public, to a want of condissertation on the forms of crys- fidence in the value and completetals, which called forth the well- ness of his discoveries. He chose merited admiration of men of to revolve them again and again in science. But while Bergman, says his mind, and wished to submit this author, reaped this honour them, according to the poets' rule, from his essay, he had omitted to to the test of a nine years' examinamention that it was the discovery tion. Though this may probably of the pupil which had furnished have partly been his motive, we the basis of all the reasonings of are willing to attribute his conduct the master. Bergman was distin- to another cause. Those only, 'we guished for his candour; he was as believe, are tenacious of celcbrity much beloved as admired; and we who are destitute of that more are rather slow to believe this solid enjoyment which results from

questionable story of bis observa- an active prosecution of the busi• tions having been founded on the ness of life, and from energetically discovery of another, which he fulfilling the duties of a man'and a took care not to acknowledge. citizen. Gahn was not a mere Gahn afterwards succeeded in ana- philosopher, deriving not only celyzing the earth of bones, and in Tebrity, but perhaps even his office, showing that it was phosphate of from his discoveries, he was the lime. The same substance, when active manager and conductor of occurring in the mineral kingdom, several manufactories, and held a has since baulked the efforts of distinguished office in the political analysts of considerable celebrity, department of a free state. It was and Gahn's success, therefore, re. probably from obtaining both adflects honour' on his sagacity. The vantage and honour from these merit of this discovery was attri- two situations, that he'was careless buted to Schcele, as it was first about that scientific celebrity, to announced to the public in his procure which is the object of so works, without the name of Gahn many intrigues, and so much writbeing mentioned. The next thing ing by men who are nothing but in which he succeeded was to re. philosophers. A n inte duce manganese toa metallic '* Gahn's father died when he was state; and though he is not now young, and left him in narrow circumstances, which compelled him In 1773, he had been elected a to exert himself; and as he was chemical stipendiary to the Royal destined to an employment about College of Mines; and from that, the mines, he took up his abode time till 1814 every chemical prowith the miners, and studied their blem the College had to decide practices till he had completely was referred to him. In 1803 and made himself master of all their 1804 a case occurred which evinced knowledge. Having, in 1770, made his skill. In consequence of the his acquirements known, by an copper sheathing of a vessel having academic thesis on the improve been corroded to a great extent, ment of iron foundries, he was there arose a prejudice against the soon afterwards appointed, by the Fahlun copper, and Gahn was apCollege of Mines, to make experi- pointed to ascertain if there were ments as to the melting of copper, any grounds for this prejudice. He at Fahlun. In consequence of his demonstrated that the copper conexperiments, and by his recom- tained no pernicious ingredients, mendation, a new method of pro- and it afterwards turned out that ceeding was immediately adopted, the copper of this vessel had not which saved a great deal of ex- been obtained at Fahlun. pense, and is followed to this day. In 1778, Gahn began his politi. He then acquired a part of the ex- cal career, being in that year retensive works at Stora Koppor- turned by the Mining Directory of berg, where he settled as superin- Fahlun to the representative body tendent, and soon had an opportu- of burghers. In the momentous nity of obtaining wealth and adding discussions which took place in the to his reputation. During the Swedish Diet, in 1778, 1809, and American war, a sudden and a 1810, Gahn took an active part, great demand was made for cop- and was always a member of the per, and a very large order was constitutional committee. In 1795, sent to Fahlun, which Gabn, at his he was chosen a member of the. own risk, though others conceived committee for directing the general it chimerical, undertook to com- affairs of the kingdom. In 1810 plete. He'succeeded, and not only and in 1812, he took an active part added to his own wealth, but gained in the measures adopted for the the increased confidence of all with maintenance of the poor, and for whom he was connected. From the promotion of agriculture. the time of his first settling at When it is considered that the Fahlun, in 1770, till 1785, Gahn mining district of Sweden which took a deep interest in the im- Gahn represented has long been provement of all the chemical distinguished for cherishing a love, works of that neighbourhood; and, of freedom, that it has possessed in conjunction with others, he es- numerous valuable privileges untablished manufactories of sulphur, changed for ages, it is eulogium sulphuric acid, and red ochre, enough for Gabn to say, that his which were a source of great emo. brother miners found in him a worlument to the proprietors. In 1780, thy representative, and a man'adethe College of Mines, as a testimonyquate to the great trust reposed in of their sense of his exertions, be- him. It must be remembered that stowed on him a gold medal. In the period when he held this trust 1782, he received a royal patent as was one of peculiar delicacy and mining master; in 1784 he was difficulty,-one when all the thrones elected a member of the Royal Aca- of Europe were convulsed: and demy of Sciences, at Stockholm; even Sweden felt the influence of and in the same year he was appoint-' that moral tempest which began at ed Assessor in the Royal College Paris. In this period of difficulty, of Mines. About the same period Gahn acquitted himself with hoalso he married Anna Maria Berg-' nour; and he is at this day as much strom, with whom he lived happily endeared to his countrymen by the thirty-one years, and by whom he ardour and disinterestedness with had one. son and two daughters which he defended their public

rights as by his scientific improve- DICTIONARY OF CHEMISTRY. ments. Gabn, therefore, was a . Argentine Flowers' OF ANTIpatriotic citizen, as well as a good MONY, An old name for antimonious man and a great chemical philoso. acid. pher; and enjoying the high ho- ARGENTUM VIVUM, quicksilver, nour acquired by the first of these mercury.. characters, might well be careless ARGIL, alumina. of that scientific celebrity which it ARGILLACeous EARTH. Another is the great object of all those who name for alumina. wonder at his carelessness to : ARGILLITE, argillaceous schistus, acquire. The end of Gahn was clay-slate. quiet and serene. His wife died ARNICA MONTANA. The flowers about 1815, and from that time to of this plant are employed in me1818, his health, which had never dicine. been robust, visibly declined. In . AROMATICS. Plants and other that year bis decay was more rapid; substances are so called when they he became weaker and weaker, and have a fragrant and pungent taste on the 8th of December, a calm and smell. Their peculiarities apand peaceful death terminated bis pear to reside in an oil which is well-spent, and, we doubt not, distilled off either with water or happy life.

spirit. Such, we believe, is ever the end *ARRACK. A spirituous liquor, of such men; and those who de manufactured from rice, and chiefly light, as we confess we do, to trace at Goa on the Malabar coast, and the beneficence of Nature, may at Batavia. read this character even in the ARRAGONITE. A mineral so called manner by which she removes man from having been first found in from the scene of his enjoyments. Arragon., She gradually blunts his percepe ARSENIATE OF POTASH, A species tions, both of pleasure and of pain; of carbonate of lime, the arsenical she takes away one tie after an- neutral salts of Macquer other, loosening all his holds of life ARSENIATES. Salts composed so gently as to be imperceptible; of arsenic acid and a base, 90 and then she wraps him in the Arsenic, A metal of a bluisksleep of death, more quietly than white colour. What is called ar. ever baby was rocked to rest by senic in commerce is a white oxide the tenderest mother. This, we of this metal, or 'arsenious acid. ? say, is her course, as exemplified

Acid. A compound of in the end of men like Watt and 100 parts of arsenic and 52.631 of Gahn.

oxygen. How calm their exit; . .

, Buster of, chloride of Night dews fall not more gently on the arsenic -". s ground, Nor weary worn-out winds expire so

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, SULPHURET OF, realgar. - soft.

Blair. “ARSENÍQUS ACID. A compound But man, thwarting Nature, of 100 parts arsenic and 34 parts plunges into intemperance; he oxygen; white arsenic, hurries to the field of blood; he : ARSENITES, Salts composed of lifts.the sword of vengeance, and arsenious acid and a base.. sacrifices the prolonged happinessA RUM MACULATUM, wake robin, of life and the balmy quietness of cuckoo point. Formerly used in natural death to some erroneous bleaching, theory of pleasure, some baneful. ASAFETIDA. A well-known med prejudice, which has been palmed dicine. It is obtained from the on him by ambition, or some ab- root of a large plant which grows surd notion of crime and its retri- in Persia. The root is cut, and bution, which leads him madly in the asafoetida issues in the form the same breath and by the same of a thick juice, like cream, which deed, both to applaud and punish becomes hard and of a brown co? the same crime. .

lour by 'exposure to the air. The (To be continued.)

stench of this substance is so ture considerably below the point great, that the Persians are obliged where water freezes, they can, of to hire ships 'expressly for convey- course, easily freeze water in the ing it, as merchants will not take midst of summer by the same it on board vessels with any other means. There are, however, sespecies of cargo.

veral other methods of accomplishAsbestos, asbestus. A silky-like ing the same effect; and as iced mineral, of which there are five wine, iced fruits, and iced creams varieties, thus named-amianthus, are great luxuries in summer, cormon asbestos, mountain leather, though an ice-house may not be at mountain cork or elastic asbestos, and land, we shall state some of these mountain wood.

methods. Take eleven drachms of Ashes. In chemistry, as in con- muriate of ammonia, ten of nitrate mon life, this term signifies what of potash, and sixteen of sulphate remains after combustion; but it of soda. They should be recently is sometimes usual in chemistry to crystallized, and contain as much understand by it only what remains as possible of the water of crystalafter vegetables have been burnt. lization without being damp. Re

ASPARAGIN, A peculiar vegeta- duce each of these salts separately ble principle, whịch forms sponta- to a fine powder, and then mix peously in asparagus juice, when them gradually in a vessel made of evaporated to the consistence of fine tin plate with five ounces of syrup. It is then in crystals, water; as the salts dissolve a de

ASPHALTUM, bitumen judaicum, gree of cold will be produced sufJews' pitch. At present bitumen is ficient to bring the thermometer a name, applied to a class of bo- below the freezing point. If a litdies, of which asphaltum is one. It tle water in a test tube be imis found in great abundance on the mersed in this mixture as the solushores of the Dead Sea, in the tion is going on, in about ten miisland of Trinadad, in Albania, nutes it will be frozen. The vessel and in numerous other parts of the in which the mixture is made world. It is found soft on the should be just large enough to shores of the Dead Sea; and it is contain it. Any thing, such as supposed that originally it was all wine-bottles, jars containing consoft, and that it grows hard by ex- serves and fruits, lemonade for posure to the air. The asphaltum sick people, &c. immersed in this of the shops is said to be different mixture, or moistened with it, and from native asphaltum, The Egyp- exposed to the action of a brisk tians employed it to embalm hu- current of air, may be rendered man bodies, and in old books it is cold in the hottest day. distinguished by the name of mumia mineralis.

QUERIES. h Assaying. The art of determining the quantity of precious

To the Editor of the Chemist. petals in any mineral or metallic SiR,Can you inform me of a memixture, by analyzing a small por

thod of blueing steel equal to the tion of it. It is a particular branch

blades of swords, and also of gildof trade, ånd there is an Assavi ing it after it is blued? This will Master to his Majesty's Mint, as be of use to me. well as numerous private assagi

I am, Sir,

Yours respectfully, masters, . da

A. R. TO MAKE ICE IN THE MIDST OF SUMMER,

1: Williams sis ... July 1st.

Sin, Ah answer to the followWe showed our readers, in our last Number, a very easy method ing queries, through the medium of

The Chemist, will greatly oblige, of producing such a degree of cold ? as even to freeze mercury, and as

*

A CONSTANT READER. that only takes place at a teñipera The best mode (if any) of extracting and preserving the juice the cast iron of which the pot is of onions in a concentrated state? made ?.

From what kind of fat is the best I have little doubt, Sir, but what tallow prepared : and what is the satisfactory answers to the above best method of preparing and pu

pue will be given, provided you deem rifying the same?

this communication worthy the attention of the Chemist.

I am, Sir, SIR, -A few days ago, whilst Respectfully yours, looking at some castings in an iron

ARSENICUM. . founder's yard, my attention was Chester, July 3. : non directed to a worn-out pot of considerable thickness. · Upon inquir

EXTRAORDINARY ENGINE ing the purpose to which a casting

FOR PROPELLING VESof sueh strength and dimensions

SELS. : was applied, I was informed, that it had been a shot manufacturer's A MR. SAMUEL BROWN has just melting-pot; and that, notwith. constructed a very curious engine, standing its unusual thickness. to be employed as the actuating (two inches in one part) it had not principle of machinery instead of been in 'use more than three months. the steam-engine. It is put into

It appears, Sir, that these pots. operation by the agency of fire, when firmly set in brickwork, are

water and air. It consists of many employed in the preparation of an parts, and is not altogether free alloy of arsenic and lead. techni- from complication; but at present cally called temper, which is afters we see nothing in its principles wards manufactured into shot. inimical to philosophy, and have This composition is exposed to the no doubt it will act, though as to its temperature of ignition to effect a power and operating cost, as comunion of the two metals : but such pared to the steam-eagine, we have had been the destructive agency of no very favourable opinion, Lon: the mixture, aided by the high don Journal of Arts and Sciences, stre temperature employed, that the

bed sides of the iron pot were com- ** EXPLOSIVE ENGINE.* pletely cut through.

Upon' inquiry I have learned. An engine of a very remarkable that the injury is principally sus

? kind is, we understand, about to tained at the surface edge of the

be : brought into publico notice, melted alloy, and as thc pot becomes

which, if it answer the expectations destroyed on the upper circum.'

of its inventor, -may ultimately ference, smaller charges are ne

supersede the use of steam-engines. cessarily thrown in until the vessel At the lower end of a small cylinis incapable of holding a sufficiency

der is placed a minute apparatus of the mixture. Perceiving, Sir,

for oil gas. As the gas is generatthat it is one of the objects of your

ed it elevates a piston, so as to aduseful Publication to promote the mit

mit as much atmospheric air as, improvement of the chemical ma

when combined with the oil gas, nufactures of the kingdom, you will

o will will render the mixture explosive. permit me, in furtherance of that When the piston has reached this Object, to propose the following

height the gas explodes, and the questionsIs the injury sustained mechanical force of the explosion by the melting-pot occasioned by is employed to drive maghinery. tlic alloy acting on the iron, and Experiments have, megnderstand, thus forming a triple compound of been actually made with this powarsenic, lead, and iron? 'Why is er, which was employed to force up the action of the alloy on the ves water to a considerable height sell confined to the edge of the EdinburghJournal of Science. won melted compound only? Is the in- ' Does this altyde to Mr. Brown's jary caused by any peculiarity in engine puldis May 196197

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