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hedral oxide of iron. A mineral with a lime and soda base was also found. The iron was most readily acted on by chemical agents, where it was in contact with these minerals ; exposure of a surface to the action of an acid not only brought them to view, but produced cavities at the points where they existed ; showing degrees of porosity influenced by their number.

“The sp. gr. of the most compact portion was 6.708. Its color was lighter gray than any sample of artificial ductile iron I have seen. Repeated bending back upon itself did not separate one fragment, but generally flaws appear and thin portions break when doubled close. The presence of the minerals imbedded is felt, when we file or saw the metal; but when heated and hammered, these fuse into slags, and the metal spreads and draws off, like the best irons, yet showing the cavities and flaws where the simple minerals had existed.

Chemical Characters. — It dissolves with effervescence in diluted hydrochloric acid, and if the acid and water are perfectly pure, the evolved gas has no odor. “200 grains were dissolved in hydrochloric acid, the hydrogen gas was passed through pure alcohol kept cool, and was then allowed to bubble through an ammoniacal solution of nitrate of silver. The alcohol had not acquired odor, nor was there any coloration or change in the silver solution. The solution of iron was turbid, but soon deposited suspended matter, which was light-gray colored ; some heavy white sandy grains, and some dark, nearly black particles, had fallen. After collecting and drying these substances,

of its parts, and generally consists of perfectly pure and malleable iron, disturbed in the arrangement of its crystalline particles by the interposition among them of a compound of iron and carbon and of graphitic carbon, besides sulphides, phosphides, and arsenides of the alkaline metals. In the ductile iron, these bodies have been nearly all removed by heat and mechanical operations, and new features impressed upon the metal. By simply removing the interposed foreign matter, by chemical means solely, crude iron is left malleable, and its particles then show their sub-crystalline forms, but not as they exist in the pure iron of the more perfect meteoric masses. All manufactured iron presents them arranged in lines and interlaced by the action of the hammer, or extended in bundles in the act of draw. ing; while the laminating mill breaks them down, shingling them over and felting together their serrated edges, in striking analogy of effect to the operations of textile manufacturing. The mechanical texture of a mass of iron cannot be shown fully by the simple step of immersion as above given, but this is sufficient to enable one to observe whether the crystals have arranged themselves as aggregates, or been broken up and disturbed by violence, and often will serve to show the kind of mechanical action employed." VOL. III.

26

they were placed under the microscope, which showed the heavier bodies to be quartz, with some facets and fragments of octohedral crystals, proved to be magnetic iron-ore. The light body was silicic acid, rendered gray by iron oxide.

“Chlorine was passed into the filtered iron solution, which, after being heated and cooled, was precipitated in a partly closed flask, by gaseous ammonia passed into it in excess. After being heated by a vaporbath, the precipitate was separated by filter and washed.

“ The filtrate and washings evaporated were reduced to a dry mass, which afforded a minute quantity of soda and lime: no other substance was present.

“ Separate parcels of the precipitate by ammonia were used for the detection of Phosphorus, Arsenic and Boron, Alumina, and other earths and oxides : a little silicic acid only was found.

" 50 grains of the filings of the iron were wet with a few drops of perfectly caustic soda solution, mixed hastily with crystals of pure nitrate of soda and chlorate of potash, and heated in a nearly closed platina crucible rapidly to bright redness twenty minutes : no deflagration occurred and the fused salts were colorless.

“ The crucible, after cooling, digested in a closed vessel with re. cently boiled pure water, gave its soluble part to the water. After subsidence, the clear Auid was added to a dilute saturated solution of lime in ammonia in one vessel, and to a dilute solution of baryta in another. These vessels were closed, and left twelve hours, and then presented nearly transparent solutions; no precipitates had fallen, but both showed the presence of silicic acid. The absence of sulphur and carbon was thus proved, and other trials confirmed these results.

Analysis. - In the following analysis, and in repetitions, different slabs of the metal were used, so as to obtain an average percentage composition of the mass.

"A solution in pure water of about one hundred and fifty grains of pure sulphate of copper was used as a medium in which the iron dissolved replaced by electrolysis the copper deposited on the negative electrode of platinum connected with a small constant battery

“ 26.30 grs. of iron solved in the fluid and 29.78 grs. of copper were deposited on the platinum, while 0.32 gr. of matter was precipitated.

“ The equivalent of pure iron being 28, the deposit of copper should have weighed 29.71; an accordance as near as the experiments allow.

“0.32 gr. of matter consisted of angular portions of quartz, frag. ments of crystals of magnetic iron-ore, and a flock of silica: no trace of carbon was observed under the microscope.

“ 26.60 grs. was the total loss from the iron.'

“ The partly ferruginous solution decomposed by an excess of hydro-sulphuric acid, evaporated and calcined, afforded barely traces of lime and soda, which in every case have been found to result from the solution of this iron.

“ 100 parts of a sample of this iron, therefore, consist of

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“ Another sample, more nearly an average, from the centre of the mass, afforded in 100 parts,

Pure iron, . . . . . . 98.40
Quartz crystals, magnetic iron ore, and sili.
cate of soda and lime, . . . 1.60

100.00 “ The little slabs which had been the positive electrodes had not disengaged a bubble of gas, which always occurs when the metals affording alkaline bases are alloyed. They also exbibited in their substance the cavities which had contained the mineral bodies found.

“I was desirous of making some comparative experiments on a specimen of iron having the characters of native iron, as distinguished from meteoric iron. My friend, Professor B. Silliman, Jr., kindly supplied me with two slips from the specimen well known as having been found at Canaan, Conn. He expressed to me at the time a doubt respecting the certainty of this mass being native iron.

“On subjecting this specimen to analytical trials, it was soon determined that it is an alloy, consisting of iron, iron and carbon, and pure graphite. “100 parts afforded

Pure iron, . . . . . . 93.057
Carbon, . . . . . . 2.666
Iron from carbon, . . . . 1.361
Graphite, . . .

2.916 100.000

“ In the arrangement of the alloy of carbon and iron, and the lamina of graphite, it differed in no respect from · Kishy' iron which has been allowed to repose in a heated state, and is unquestionably an artificial iron, – a product of the blast furnace.”

Professor Agassiz' said that he had received, through the kindness of Dr. Green, of Commodore Perry's Japan Expedition, the bag containing the immature young of a viviparous fish from Japan. He regretted that the whole of the parent fish had not been preserved, but he hoped to be able from the embryos to make out the characters of a new genus, which may be regarded as the Asiatic representative of this interesting type. The specimens were from the shores of Simoda.

Professor J. P. Cooke gave in detail the processes by which he had obtained perfect octohedral crystals of arsenic. He was led to do so by the fact that their genuine character had been called in question.

Dr. A. A. Hayes confirmed, from his own knowledge, the fact of the production of such crystals in other ways.

Four hundred and eighteenth meeting.

October 9, 1855. — Monthly Meeting. The President in the chair.

The Recording Secretary, in behalf of the author, presented the following paper, viz. : “Descriptions of New Species of Fossils, from the Cretaceous Formations of Nebraska, with Observations upon Baculites ovatus and B. compressus, and the Progressive Development of the Septa in Baculites, Ammonites, and Scaphites. By Professor James Hall, of Albany, N. Y.”

Professor J. P. Cooke exhibited and explained a printed chart of his classification of the chemical elements. The plan was the same as one already published by him, with some modifications.

Four hundred and twentieth meeting.

November 14, 1855. — STATED MEETING. The President in the chair.

The following gentlemen were elected Fellows of the Academy, viz. :

John C. Gray, of Boston, Professor James Russell Lowell, of Cambridge, Professor Francis J. Child, of Cambridge, and Richard Greenough, of Boston, in the Section of Literature and Fine Arts.

Rev. William A. Stearns, D. D., of Amherst, in the Section of Philosophy and Jurisprudence.

Professor Albert N. Arnold, of Newton, in the Section of Philology and Archæology.

The following, nominated by the Council, were elected Foreign Honorary Members, viz. :

Dr. Fr. W. A. Argelander, of Bonn, in the Section of Astronomy.

Victor Regnault, of Paris, in the Section of Physics and Chemistry.

L. D. Vicat, of Paris, in the Section of Technology and Engineering.

Richard Owen, of London, in the Section of Zoology and Physiology.

Sir Benjamin Brodie, of London, and P. Rayer, of Paris, in the Section of Medicine and Surgery.

Archbishop Whately, of Dublin, and Victor Cousin, of Paris, in the Section of Philosophy and Jurisprudence.

Franz Bopp, of Berlin, and Friedrich von Thiersch, of Munich, in the Section of Philology and Archæology.

François Guizot, of Paris, in the Section of Political Economy and History.

Professor Gray laid before the meeting a bronze medal commemorating the three eminent botanists, Bernard, Antoine Laurent, and the late Adrien de Jussieu : presented by the Jussieu family.

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