— AecordiDg lo the committee on telegraph ap- paratus at the Philadelphia electrical exhlbitioo, the possibility of employing a single conductor for the slmultjtneons Iransmisaion o( two or more sets of telegraphic signals appears lo have originated with Moses 6. Farmer of Boston, Mass., about the year 1652. Mr. Farmer nttached to each end of the line a rapidly revolving commutator or distributer, The two distributers, when caused to revolve synchronously and in unison, served to bring the line successively and simultaneously into connection with a correspond- ing series of short branches at each terminus, in each of which branches ordinary telegraphic apparatus was inserted and operated in the usual manner. Thus the current through each pair of corresponding branches at either station, while apparently continu- ous, actually consisted of intermittent but rapidly recurring synchronous pul- sations. Sir. Farmer suc- cessfully e^cperimeoted, upon a small scale, upon the wires of the municipal telegraphic lines of Boston In 1SS2. Nothing of per- manent value, however, re- sulted from the experiments at that dale, the difficulty ofmaintainingtheabsolute synchronism required for operating for any consid- erable length of time being apparently insuperable.
— L' Astronomie reports a most remiirkable halo seen by M. D. Luzet on the nth of January last at Orleans, France. There were no clouds in the sky, simply a light mist, and the temperature was ~ 1" C. At 12.40 P.M. a very bril- liant circle, with a radius of 2*.'°, appeared around the sun; and, at the two extremities of the horlxuntal diameter of this circle, two while spots were formed, which, gradually increasing In intensity, became very brilliant at I2.&S. Above, and not touching the cir- cle, was a rainbow, which gradually faded out at its extremities Inlo the blue sky. The red of this bow W39 oulslde, the violet within, and the brightness and distinctness of llie tints were very marked.
— The recent Are In the capitol at Trenton, N,J., inflicted considerable loss on the geological collections of the stale. The suites of typical rocks from the several [ormatlojis, and large collections of Iron ores, clays, marls, and soils, were all lost; and some old state maps, now out of print, were destroyed. The old collection of B. D. Rogers was lost; that of Dr. Ettchell was saved. Fortunately, a large number of selected representative specimens of rocks, ores, woods, etc., escaped by tielng in the state exhibit
����now at New Orleans; and while the loss, u a whole, I is a serious one, it is not irreparable. In the con- 1 tinned prosecution of the state survey. It will be poi-B Bible In time to make a fuller and more representative I collection than that which Is destroyed. Loped that the new rooms, which we understand an I to be provided for the museum, wilt be of safer coo- I struciion, and. If necessary, isolated to make tbemf
— Tbe Echo du Japan reports the arrival in Japan, ' at the beginning of the year, of Joseph Martin, a French traveller, who had just been exploring the parts of Siberia hitherto very little known. His principal journey was from the Lena to the Arnonr, across IheStanowii chain of mountains. During tik J explorations he was abta'l to make geographical aolj geological col" which are intended tortlw Paris museums. In con- sequence of hardships en- dured oa the journey, two of his native follow era 1 died, and one lost his re*, a
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��— Mr. Ellery of the Mel- bourue observatory taken the necessary steps toward the oi^nlialion of a small expedition to llie southern coast of the north island of Xew Zealand, In the coming September, to observe the total eclipse of the sun, which oi tbe Blh of that The track of the line total eclipse lies almoM wholly in the South Pacille Ocean, and New Zealand is the only land croaied by It; the duration of to- tallly lasting about Iwa
minutes at the spot most favorably located for
observation.
— The legislature of New York has passed aa! appropriation of twenty-live thousand dollars for Slate survey.
— A bill has passed tin? Wlsconaiu legislature f vlding for the education of deaf-mutes. Hitherti there has been no special provision for their insuta*^ Uon.
— The topographical mapof New Jersey, to which ■! tentlon has been called already several times, has in advanced to the point of Issuing six sheets in all. They are fine pieces of work, of which the state may JiuUf be proud. ElevoQ more slieets remain to be done.
— We neglected to state in our last that the fie> J simile of the map by General Gordon, of the r from SuakIn lo Berber, was published by I Stanford, 6fi Charing Cross, London.
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