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428 



NATURE 



\_March 6, 1879 



molten trachyte down to 800,000,000,000 years afterwards, that 

 is, long after the present era. 



Royal Microscopical Society, February 12. — Annual 

 meetin<^. — H. J. Slack, president, in the chair. — The report of the 

 council was presented and read by the Secretary, — The president 

 read his annual address, in which the oil immersion objectives 

 and the recent discussion on fermentation were refen'ed to. — 

 Dr. L. S. Beale, F. R.S., was elected President. — Ilerr Petzold's 

 slides of insects, kindly lent by the editor of Nature, were 

 exhibited, also catoptric immersion illuminator, by Mr. Stephen- 

 son, and microscopes by Mr. Crisp. 



Boston, U.S.A. 



American Academy of Arts and Sciences, February 12. 

 — Hon. Charles Francis Adams in the chah:. — Prof. Pickering 

 announced the completion of the observations of the zone 

 assigned to the Harvard College Observatory in the revision of 

 the Durchmusterung oi Argelander. The observer, Prof. W, A. 

 Rogers, has devoted in this work a large portion of his time for 

 the past eight years. The stars are all included between 49° 50' 

 and 55° 10' N., and number over 8,000. The accuracy required 

 has made the work very laborious, the total number of observing 

 hours being greater than was required in the Catalogue of 

 Argelander, containing the approximate places of over 300,000 

 stars. The deductions are still to be made, and will require 

 some years. — Prof. N. S. Shaler read a paper on the explosion 

 of coal-dust in mines, and suggested that a solution of 

 calcium chloride, which is obtained at no other expense 

 than the cost of prepai-ation from the water of salt works, 

 be driven in the form of spray against the walls of the mine in 

 order to fix the dust in a deliquescent substance upon the walls. — 

 Prof. Asa Gray read a paper on the characters of some new 

 genera and species of plants, chiefly of California and Oregon. 

 — Mn Thomas P. James made some remarks upon American 

 bryology and some new species of mosses described by himself 

 and Leo Le?quereux. — Mr. N. D. C. Hodges presented a paper 

 on a new absolute galvanometer. The current is measured by 

 its effect in changing the time of vibration of a magnet with its 

 axis parallel to that of the coil. Mr. Hodges also presented a 

 method of determining the reduction-factors of a tangent gal- 

 vanometer for all deflections when the value for any one is known. 

 By measuring a current by the deflection and then with the same 

 coil and magnet, by the change in time of vibration, the ratio 

 between the reduction-factor of the instrument when the magnet 

 makes any angle with the plane of the coil to its value when the 

 magnet is perpendicular to the coil may be found. 



Paris 

 Academy of Sciences, February 24. — M. Daubre'e in the 

 chair. — The following papers were read : — On the induced 

 currents resulting from movement of a bobbin across an electro- 

 magnetic system, by M. Du Moncel. Inter alia, the direction 

 of induced currents caused by a given movement of a bobbin be- 

 fore a magnetic pole may be diametrically opposite, according as 

 the movement is tangential or normal to the pole, and the mag- 

 netic core on which the bobbin glides is in contact with the 

 inducing pole, or distant from it. — Observations on M. Plante's 

 recent work, "Researches on Electricity," by M. Becquerel. 

 These researches relate to secondary currents. — On 'the hemi- 

 hedric forms of alums, by M. Lecoq de Boisbaudran. — Resist- 

 ance to change of state of crystalline faces in presence of their 

 mother-water, by the same. The passage from a state of very 

 slow dissolution to one of very slow growth does not take place 

 suddenly ; each face re^ts intact, while the mother-water varies 

 within certain limits. There is no mobile equilibrium or exchange 

 of molecules between a crystalline face and its mother -water, but 

 merely erosion or continuous deposit, and, between the limits of 

 resistance to change of state, neither erosion nor deposit. The re- 

 sistance to changeof stateis modified independently for each system 

 of faces. — Experiments on a modification which has been made 

 in the sluice of Aubois, permitting the suppression of the alter- 

 nate motion of vessels in the lock, by M. de Caligny. — Reflec- 

 tions on M. de Lesseps' communication regarding contagion of 

 the plague, by M. Bouillaud. Considering the plague conta- 

 gious, he says the important problem now is to ascertain the 

 nature of Xht. principle or agent by which it is communicated. — 

 M. de Lesseps presented the reports he had drawn up for the 

 Alexandrian authorities during the plague in Egypt in 1834-35. 

 — M. Stephan was elected Correspondent in the Section of 

 Astronomy, in place of the late M. Hansen, of Gotha. — On 

 latex during the germmative evolution of Tragopogon porrifoHus, 



&c. (continued), by M. Faivre. — Observations of eclipses of 

 Jupiter's satellites, made at the observatory of Toulouse in 1878, 

 by M. Baillaud. — Direct photography of solar protuberances 

 without use of the spectroscope, by M. Zenger. He puts on 

 the sensitive plate, before a very short exposure, a solution of 

 pyrogallic acid and citrate of silver, and uses a layer which 

 absorbs all the rays composing the light of the corona and 

 the solar protuberances. — Geometrical laws of deformations 

 produced by a force applied at a point of an indefinite 

 solid, and calculation of the error fallen into, when, according 

 to the principles of classical mechanics, one conceives this point 

 of appHcation displaced by a certain quantity in direction of the 

 force, by M. Bou sinesq. — Projection of molecular shadows, by 

 Mr. Crookes. — Action of different coloured lights on a layer of 

 bromide of silver impregnated with different organic colouring 

 matters, by M. Cros. — On plates sensitised with tincture of 

 mallow or black-currant, the direct spectrum of the Dnunmond 

 lamp is inactive in all the middle green, while the red and violet 

 extremities are very active. With carthamine, again, the middle 

 part is most active. With chlorophyll the action continues 

 throughout the visible spectrum and a little beyond it, presenting 

 several minima and maxima. M. Becquerel pointed out that 

 these researches had been to some extent anticipated. — On the 

 production of crystallised chromate of baryta, by M. Bourgeois. 

 This gives some new results by the method of calcining an 

 alkaline chromate with the chloride of the metal which is 

 desired to enter into the saline combination. — On the composi- 

 tion of beer yeast, by MM, Schutzenberger and Destrem. 

 Yeast contains complex compounds both hydrocarbonised and 

 proteic, formed like glucosides, and easily decomposed by acids* 

 and alkalies. — On pyrogenic carburets of American petroleum, 

 by M. Prunier. He has obtained carburets with considerably more 

 carbon than any compounds hitherto known {97 per cent., the 

 highest previously 95 per cent.). — On glycide, by M. Hanriot. 

 — On the generation of aniline-black by chromates in presence 

 of chlorates, by M. Grawitz. He disproves M. Witz's recent 

 assertion against this. — On various selenides of lead and copper 

 from the Cordilleras of the Andes, by M. Pisani. — On the 

 presence of a segmentary organ in endoproct Biyozoa, by M. 

 Joliet. — On the segmentary organs and the genital glands of 

 sedentary poly chse tons Annelides, by M. Cosmorie. — On the 

 scales of osseous fish, by M. Carlet. He describes the effects 

 of coloui'ing with picro-carminate of ammonia, and of subjecting 

 to polarised light. — On the mode of employment of telephones 

 at the Artillery School of Clermont, by M, de Champvallier. 

 The success realised is attributed to the method of regulating 

 the position of the magnet. The milled button for turning the 

 screw has at its base a pointer (at right angles to the axis) which 

 moves over a circle of copper. The positions of this pointer for 

 distinct transmission one way or the other are noted. 



CONTENTS Pagb 



Coal AND CoAL-MiNES. By Prof. T. E. Thorpe, F.R.S 405 



The Morphology op the Echinoder.ms 



Our Book Shelf: — 



"Jornal de Sciencios Mathematicas Physicas e Naturaes;" 



" Giornale di Matematiche " .... 407 



Wiltshire's " History of Coal" 407 



Letters to the Editor :— 



Quarantine in Italy. — Prof. T. Caruel 40$ 



Captain Cook's Accuracy. — Rev. S. J. Whitmee 409 



Cook's Collections. — A. B. Mayer . 499 



Magnetic Storm, May 14, 187S. — Henry C M.\nce . . . . . 405 



Intellect in Brutes. — Arthur Nicols ; W. P. Buchan ; Dr.. ' 



Hknry Muirhead ; Dr. John Rak^ A. J, A. ; jC. 3W.; STSiCKf . 



r.^'t'? ■ ^ Wtd t^ ^rv:riaf«:> «/r- "!«-?■••. ^ 



Parhelia. — E. W. Pringle , . . ... -...rf .„ .^i .„.?,... . • — 

 Unscientific Art.— E. W. PRINGLK '.-.I', i .'.''.'■.■ . . 



Bees' Stings. — Prof. A. H. Church 4IB 



A New Process in Metallurgy 4JW 



On THE Freezing OF Lakes. By J. Y. Buchanan (ff7M ZP/a^rawi) -4;^* 

 On the Bursting of the Gun on Board the " Thunderer." By 



Prof. Osborne Reynolds, F.R.S '4*4 



Moseley's Naturalist on the " Challengkr." By Prof . E. Rav 



\.A.nK.E.sTUB., ¥ .V..S. (With Illustratiims) .>•,*■ Trvlr/-. . . • 4T5 



Meteorological Notes •.,...... 4»9 | 



Our Astronomical Column :— 



Brorsen's Comet 430 1 



Minor Planets 4»« I 



Variable Stars 4** [ 



Geographical Notes 4*fj 



Notes 43*1 



The Physical Nature of the Sun. By Dr. Gruss .... . . 434 j 



The Structfre AND Origin of Limestones. By H, C. toKBY,. 



F.R.S .• ,m\ 



University anb Educational Intelligence m\ 



Scientific Serials 4*] 



Societies anb Academies ^*\ 



