140 



NA TURE 



[Dec. 16, 1875 



paper is carried. Tlie other connections are as follows : — The 

 current passes from one pole of battery to spring of releasing 

 apparatus (which is also connected with one terminal of a separate 

 condenser), thence through the bullet to the fixed portion of the 

 clip, and by a wire to the lower table, which is also in electrical 

 connection with the face of the electro-magnet which releases the 

 bullet, in order that the current may be completed immediately 

 the falling body is released. From this table the current passes 

 through an adjusting screw to one terminal of the primary wire of 

 the induction coil which is connected with the other condenser 

 terminal. The other pole of the battery is connected with the 

 primary. The spark in each case is caused by the breaking of 

 the current which takes place when the bullet is released 

 and when it strikes the table, the perforations in the black 

 paper of course being made in the trace produced by the 

 tuning-fork. It is hardly necessary to mention that the re- 

 leasing electro-magnet is worked by one or two independent 

 cells. The author considers that with a fork making sixty-four 

 complete vibrations in a second the error, in determining an 

 interval of not more than two or three seconds, should not 

 exceed -s^^th of a second, and that with a more rapidly vibrating 

 fork probably much greater accuracy might be attained. Mr. 

 Lodge made four experiments before the Society with falls of 

 2 ft. and I fr., from which the value of gravity was found to be 

 32'2i. Prof. Guthrie inquired whether the instrument was sen- 

 sitive to the influence of temperature on the time of vibration of 

 the tuning-fork. Mr. Ladd suggested that the pressure of the 

 marker on the end of the tuning-fork might hinder its vibration, 

 and referred to difficulties which Capt. Noble had met with in 

 the working of his chronograph. Mr. Lodge stated that experi- 

 ments had only been niade in a laboratory having a fairly equable 

 temperature, and that therefore the effect of considerable changes 

 of temperature had not been ascertained. He considered that 

 the slight resistance referred to by Mr. Ladd would rather tend 

 to dimmish the amplitude of vibrations than to change their 

 number per second. — Prof. McLeod then described and exhibited 

 an arrangement for ensuring that the charge giveir to a Leyden 

 jar shall not exceed any fixed limit. Through a cork in the 

 upper tnd of a bell-glass passes a brass rod, insulated through 

 its entire length by means of a glass tube, through which it 

 passes freely. To the upper end is attached a brass knob, and the 

 lower end is pointed and provided with a screw-thread, so that 

 it can be set at any distance within, or through, a hollow brass 

 ball, perforated below and rigidly fixed to the glass tube. Within 

 the bell-glass is a loose cage of perforated sheet zinc and a vessel 

 containing strong sulphuric acid. The whole stands on a metallic 

 plate to secure a good earth connection. The action is as fol- 

 lows : —If the rod be screwed down so that the point projects 

 through the hollow ball, the upper knob and lower metallic 

 plate being connected with the two poles of a Holtz machine, 

 only short sparks can be obtained, because a large amount of 

 electricity escapes at the point ; but if the rod be raised so that 

 the rod barely enters the hollow ball, at the top, no escape takes 

 place from it, and the machine will give its full length of spark. 

 By varying the position between these two extreme limits, any 

 required length of spaik or amount of charge for an interposed 

 Leyden jar can be obtained. 



Entomological Society, Dec. i. — Sir Sidney Smith 

 Saunders, C.M.G., president, in the chair. — Mr. W. A. 

 Forbes exhibited a variety of the Burnet Moth (Zygcrna 

 filipindulce), with yellow spots, of which he had bred a 

 number from larvDs taken near Winchester. — Mr. Champion 

 exhibited some rare British Coleoptera. — Mr. William Cole 

 exhibited carefully-executed drawings of the pupa; of a species 

 of the Dipterous genus Ephydra, which he had taken clinging 

 to the stems of grass, in brackish water, near Southend, Essex. 

 — The President referred to the numerous parasites found on 

 bees of the genus Osmia, and remarked that M. Jules Lichten- 

 stein had recently obtained Zonitis prausta from the cells of 

 Osmia iridentata ; and likewise Euchalus vetitsta, Duf., from its 

 desiccated adult larvae, in the same way that Halticdla osmicida 

 effects its metamorphosis, thus making the thirteenth parasite 

 recorded as infesting this particular species of bee. — A paper 

 was communicated by Dr. Burmeister, of Buenos Ayres, giving 

 a description of a new genus belonging to the family Scaritida: 

 (nearly allied to Clivina), taken on the shore of the river Uru- 

 guay, near the town of Concordia. 



Paris 

 Academy of Sciences, Dec. 6. — M. Fremy in the chair. — On 

 the constitution of phosphates, by MM. Berthelot and Louguinine. 



— Atmospheric perturbations of the hot season of 1875, '^7 M- 

 Belgrand. — On the colouring matter of fruits of Mahonia, and the 

 characters of the wine these fruits give by fermentation, by M. Is. 

 Pierre. — On the astronomical phenomena observed in 1597 by 

 the Dutch in Novaya Zemlya, by M. Baills. — Note on the double 

 touch process of magnetisation, byM. Gaugain.— On the tempera- 

 ture of elevated layers of the atmosphere, by M. Mendeleeff. The 

 temperatures observed there are constantly higher than those 

 calculated ; this is accounted for by aqueous vapour, — On the 

 transparence of flames and of the atmosphere, and on the visi- 

 bility of scintillating lights, by M. Allard. From experiment he 

 adopts o*8i as mean value of the coefficient of transparence of 

 flame, referred to the centimetre of thickness traversed. The 

 absolute intensity of flame increases more rapidly than the 

 weight of oil consumed, but the amount of light absorbed in 

 passage of rays through the flame increases still more rapidly. — 

 On the distribution of magnetism in circular or elliptical steel 

 plates, by M. Duter. — On some properties of gallium, by M. 

 Lecoq de Boisbaudran. This is noticed fully elsewhere. — 

 Note on a derivative by hydratation of cellulose, by M. Aime 

 Gerard. — Researches on the constitution of albuminoid matters, 

 by M. Schutzenberger. — On the development of the fruit of 

 Chaetomiuiii, and the supposed sexuality of Ascomycetes, by M. 

 van Tieghem. — On new fossil pieces discovered in the phos- 

 phorites of Quercy, by M. Gaudry.^ — On the virulent state of 

 blood of healthy horses, killed by falling or asphyxia, by M 

 Signol. The blood taken from the body aiter sixteen hours proves 

 rapidly fatal to goats or sheep inoculated with it (twenty-four 

 drops). Motionless bacteridia are present, but there is no sign 

 of putridity. — Discovery of the 157th small planet at Marseilles 

 on Dec. i. Ephemerides and observations of planets lately 

 discovered, by M. Stephan. — Observations of planets (152) 

 and (154) made at the Paris Observatory, by M. Prosper 

 Henry. — On the isochronism of the spirals of chronometers, 

 by M. Caspari. — Note on the distribution of magnetism in 

 the interior of magnets, by MM. Treve and Darassier. — 

 On the fermentation of fruits, by MM. Lechartier and Bellamy. 

 — On panification in the United States, and the properties of 

 hops as ferment, by M. Sacc. — On the presence, in present 

 seas, of a type of Sarcodaria of the secondary strata, by 

 M. Fischer. — On larval forms of Bryozoa, by M. Barrois. 

 ■ — On the organisation of Acarians of the family of Ga- 

 masides ; characters showing that they form a natural transition 

 between hexapodan insects and Arachnida, by M. Megnm. — 

 Nidification of the rainbow fish of India, by M. Carbonnier. — 

 On the ferns and Lycopodiacen; of the islands St. Paul and 

 Amsterdam, by M. Fournier. — On the influence of stripping off 

 the leaves of beet on production of sugar, by M. Corenwiuder. 



BOOKS AND PAMPHLETS RECEIVED 



British. — T he Native Races of the Pacific States of North America. 

 Vol. iv. : Hubert Howe Bancroft (Longmans). — The Movements and Habits 

 of Climbing Plants: Charles Darwin, M.A., F.R.S (Murr.^y i.— iVlcu.cinal 

 Plants. Part 2: R. Hentley, F.L.S., and H. Trimen, MB., F L S. 

 (Churchill). — Milk in Health and Disease : A Hutchinson Smee (Newman). 

 — Magnetism and Electricity : F. Guthrie (Wm. Collins, Sons and Co.) — 

 Hermann's Human Physiology. Translated by A. Ganigee, M.D , F. R.S. 

 (Smith and Elder). — Pyrology, or Fire Ctiemi.stry : Wm. A. lioss (Spni). — 

 Timber and Timber Trees : rh»mas Lasletl (Macmillan). — Discoveries and 

 Inventions of the Nineteenth Century : K. Routledge, B.Sc, F.C.S. (Kout- 

 ledge). 



CONTENTS Pace 



Haeckel's History of Creation. By P. H. P. S 121 



Burton's Gorilla Land AND THE Congo (ff7M ///«j^rrt/j£;«:i) . . 123 



The German North Se.a. Commission. By E. P. W 125 



Our Book Shelf :— 



" The Origin of the Sun's Heat and the Chemical Constitution of 



the Matter of his System" 12(5 



Letters to the Editor : — 



Theophrastus versus Millington. — A. B. C. 127 



Estimation of Fractions.— W. M. Flinders Petrik 127 



The Late Dr. von Willemoes-Suhm. — J. C G 129 



Seasonal Order of Colour in Flowers. — C. E. Heron Rogers . . 129 

 Our Astronomical Colu.mn : — 



Atlas Pleiadum, 2 453 129 



The " Gegenschein " of the Zodiacal Light 129 



The Comet of 1729 ... 129 



Rutimeyer on Traces of Man recently discovered in the Inter- 

 Glacial Coal-Beds of Switzerland, By J. L 130 



The Theory of " Stream Lines " in Relation to the Resistance 



of Ships, III. By Wm Froudb, F.R.S. (W^i//j ///2«/rai;w«i). . 130 



The Channel Tunnel — Submarine Exploration.s. By W. Topley 133 



Notes ^34 



On some Properties of Galliu.m 136 



Scientific Serials ■ i37 



Societies and Academies 138 



Books and Pamphlets Rbcbivkd , . 14° 



