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“ Whereas this Academy has recently received intelligence of the afflictive event which has deprived it of its illustrious Foreign Member, and the world of a great master in mathematical, astronomical, and physical sciences,
“ Resolved, That the American Academy of Arts and Sciences would unite with other learned institutions throughout the world in expressing its sense of the immense loss sustained by Science in the death of Carl Friedrich Gauss.
“ Resolved, That the Academy has regarded with pride and admiration the long and brilliant scientific career of the venerable · father of sciences, whose usefulness has been permitted to extend to the last hours of a life longer than is ordinarily permitted to mortals, although it closed with the full brilliancy of its noon.
“ Resolved, That the Academy offers its condolence to the bereaved family of the illustrious dead.”
Dr. C. T. Jackson exhibited drawings of a microscopic view of a fungus on the surface of a yellow rose.
Dr. Jackson also read the following analysis of water from the Sacramento River, California.
“7 cubic centimetres, equal to 2) fluid ounces nearly, gave of solid matter 0.4 grains. This was found to consist of Silicic Acid,
0.08 Soda and Chloride of Sodium,
0.22 Sulphate of Soda,
traces. Organic matter,
0.40 This water contains no salts of lime."
The election of officers was held in the usual form, and the following were chosen :
of Class I.
: Joseph LOVERING,
J. I. BOWDITCH,
of Class II.
of Class III.
The several Standing Committees were appointed, on nomination from the chair, as follows:
Henry L. Eustis,
Committee of Publication.
J. P. Cooke, JR.
THOMAS T. BOUVÉ.
Four hundred and sixteenth meeting.
August 8, 1855. — QUARTERLY MEETING. The PRESIDENT in the chair.
The Recording Secretary read a communication addressed to him by J. J. Dixwell, Esq., requesting in behalf of Dartmouth College that the Publications of the Academy be presented to that Institution.
On motion of Dr. A. A. Gould, seconded by Professor Asa Gray, it was voted, that, in accordance with the request of Mr. Dixwell, the new series of the Academy's Transactions be presented to Dartmouth College.
Four hundred and seventeenth meeting.
September 11, 1855. — ADJOURNED QUARTERLY MEETING. The PRESIDENT in the chair.
Professor Joseph Henry, of the Smithsonian Institution, addressed the Academy on the subject of the induction of electrical currents at great distances from the primitive current, and on the oscillating movements which he had detected in these currents, giving a positive or negative character at any given point at different times. He also gave an account of the numerous experiments he had made to establish the facts which he had announced.
Dr. A. A. Hayes remarked, that
“ The facts communicated by Professor Henry are of high interest and importance, in their bearing on any theory of electrical action. The phenomena presented in the observations of Professor Henry correspond, in a remarkable manner, with those taking place when a hydro-electric current acts on a conductor of the first class. In the case of a continuous polarization, the central parts of such a conductor exhibit no power of decomposition, even when the current is feeble. A simple experiment, which illustrates this condition of a polarized conductor, may be made by immersing a curved wire in a solution of metallic salt, the metal of which can be displaced by the metal of the curved wire. If a wire of soft bright iron, bent in the form of a horseshoe magnet, have its bend barely dipped into an acidulated solution of sulphate of copper, the copper will be deposited on it as it would be on a straight wire. But if the curved wire be lowered into the solution, or if at first it be at once immersed, the deposition of copper by displacement occurs at the free extremities of the wire and extends towards the bend from them. It ceases, however, before it reaches the bend, or central part, which never receives more than the slight coating due to the instant exposure in immersing it. This experiment may be varied by modified curves of the wire ; but however numerous the forms of the bends, the central part of each wire or plate is null in its action as an electrode."
Dr. A. A. Hayes read the following communication on a specimen of native iron from Liberia, Africa :
" It is with pleasure that I submit to the inspection of the Academy a specimen of native iron from Liberia, believed to have been taken from the tract of country bordering the St. John's River, recently acquired by the New Jersey colony. This specimen was placed in my hands by Rev. Joseph Tracy, Secretary of the Massachusetts Colonization Society, for examination, and its physical characters at once arrested my attention, as differing from those of any artificially produced iron. As I deem the discovery of native iron existing unalloyed a matter of much interest to naturalists and chemists, it is proper that the evidence on which the statement rests should be submitted somewhat in detail. In the African Repository, Vol. XXX. No. 8, August, 1854, at page 240, is a letter from Rev. Aaron P. Davis, a resident missionary at Bassa Cove, from which the following extracts are taken.. " I send you a piece of African ore, just as dug from its native bed, or broken from among rocks. I have seen and conversed with a number of natives, who affirm that it is actually the pure ore, or just as taken from its native bed. I obtained a piece through Hon. George L. Seymour, who had tried in vain to dissect it: and I being of that craft, he brought it to my shop for that purpose. When he brought it, it appeared like a craggy rock, of yellowish color on its surface, and, with a very small exception, it could not be separated but by heat and hard pounding with my largest sledge-hammer and a chisel prepared for the purpose. I also send you a teaspoon which I made of some of the ore, which in its crude state is supe. rior to the iron brought here for sale by English merchant-vessels.' 'I am told by the natives that it is plentiful, and about three days' walk from our present place of residence (Bassa Cove): it is gotten by digging and breaking rocks. It is also said to be in large lumps. In these parts the natives buy no iron, but dig it out of the ground, or break the rocks and get it, as the case may be.'
“ The largest specimen before you, when received by me, bore on one side the impress of the chisel, the coarse fracturing of a tough metal, and marks of oxidation by fire; it was further identified by William Coppinger, Esq., of Philadelphia, as the piece received with the letter of Mr. Davis. Mr. Coppinger gave the specimen to Rev. H. M. Blodgett, who sent it to Rev. Joseph Tracy, from whose hands I received it. Soon after I had expressed to Mr. Tracy my belief that the specimen was native iron, he placed before me a large amount of written evidence, showing that malleable iron, sufficient in quantity to meet the wants of the natives, is obtained by heating and then by fracturing the rocks of the country. The writers use the term ore incorrectly, as Mr. Davis does, apparently in the belief that iron ores increasing in richness become malleable. The metallurgical knowledge of the natives is so limited, that they are unable to produce copper from the carbonate of copper (malachite), which they carry five or six hundred miles as a medium of traffic; while their weapons of iron, which I have examined, show the characters of native iron, after it has been heated and hammered.
“ Physical Characters. — On developing the internal structure of the mass of iron, by immersion for a few moments in strong nitric acid, and immediately after washing in a mixture of limc and water, it was apparent that the minute crystalline particles were arranged in a manner closely resembling those of the pure iron * in meteoric iron, and entirely unlike the particles in artificial iron.
“ Where the mass had been heated, and had received blows, there was an approach to the appearance presented by artificial iron, but the internal parts, and nearly the whole of the mass, showed no marks of percussive or laminating action. By the more complete development of the structure, certain points appeared which were evidently extraneous matter. Under the microscope these points showed crystalline minerals, which when separated proved to be quartz and octo
“ The character which is here noted has a higher value in a research of this kind, than would have been inferred from a cursory examination. In a description of the remarkable meteoric iron, published in the American Journal of Science, November, 1844, I alluded to the fact, that these masses are not made up of iron alloyed with nickel and other metals, but consist of pure iron, through which are mixed portions of an alloy of nickel and iron, and iron and nickel and other bodies, as distinct electro-negative matter, in relation to the pure iron. The Texas meteoric mass and the small particles of the Western meteorolite had the same mechanical constitution. Since the first publication of my results, these researches have been extended, so as to include the metals of commerce and the well-known alloys. The numerous analyses made on these forms of matter have not yet shown an exception to the condition, that the metal existing in the largest proportion is in part pure; while one, two, three, or more alloys may exist, distributed through it. When we take the results on a mass of crude iron in the state of pig-iron, and on portions of the less and more malleable iron, of the different steps of the manufacture, we not only pursue the constituents chemically, but the mechanical state of the iron is at the same time open to view. A mass of pigiron thus becomes associated with meteoric iron, in the mechanical arrangement