The value of v given by the experiments here described is 293 x 108 centims. per second. The method employed was that of obtaining an absolute electrostatic and an absolute electromagnetic measurement of the same electromotive force. vis defined as the ratio of the units of quantity in the two systems; but it follows from the definition of electro-motive force, that v is also the ratio of the units of electromotive force in the two systems.

The electromotive force, or the difference of potentials between the two poles of a constant Daniell's battery, was measured electrostatically by means of Sir William Thomson's absolute electrometer. The absolute electromagnetic value of this electromotive force was given by the effect of the current which it maintained in the circuit of an electrodynamometer. The determination of this value depended on the resistance of the electrodynamometer-circuit, which was reckoned in terms of the absolute value of the British-Association standard unit of resistance. Any correction which may hereafter be found to be applicable to the absolute value of this standard coil, as measured at King's College by Professors Clerk Maxwell, Balfour Stewart, and Fleeming Jenkin, must be applied to the value of give above.

The comparisons made in 1867 and 1868 by Mr. King gave as the mean value of v, 284'6 × 108 centims. per second. The experiments made in 1870 with the new absolute electrometer give as the mean result v=294'5 × 108 centims. per second. The result of the later observations made under much more favourable circumstances was v=292'4 x 10 centims. per second. The latest observations (1872) furnish the most probable value of v, 293 × 108 centims. per second.

Zoological Society, June 3.--Viscount Walden, F.R.S., presicent, in the chair. The secretary read a report on the additions that had been made to the Society's collection during the month of May. The following, among other objects, was exhibited :The figure of a supposed new species of Chelodina from the Burnett River, Queensland.-A letter was read from Dr. George Bennett, F.Z.S., referring to the supposed existence of a species of Tree Kangaroo (Dendrolagus) in Northern Queensland, some such animal being apparently well known to the blacks of Cardwell.-A memoir was read by the Viscount Walden on the birds of the Philippine Archipelago, founded mainly on the recent collections of Dr. A. B. Meyer, but containing a complete account of all the known species of Philippine birds, and remarks on their geographical range. The total number of known Philippine species was estimated at 215, but a large number of the islands iemained unexplored.-A paper was read by Sir Victor Brooke, Bait., F.Z.S., on the antelopes of the genus Gazella, of which 20 species or "persistent modifications," as the author preferred to call them, were recognisable. Sir Victor Brooke entered at full length into the questions connected with the present geographical distribution of the group, and its supposed descent from pliocene and miocene forms.-Mr. A. Ĥ. Garrod read a paper on the pterylosis and on some points in the anatomy of the Guácharo (Steatornis caripensis) and showed that this singular bird must be constituted a family per se, related in some respects to the Caprimulgida and their allied forms, and in other respects to the Owls (Striges).

Chemical Society, June 5.-Dr. Odling, F.R.S., president, in the chair.-Six communications were read before the society, the first being "On the dioxides of calcium and strontium," by Sir John Conroy, Bart., in which the author gave the method of preparation and properties of these substances. -Mr. T. Wells then described a new form of ozone generator which gives abundance of ozone and has the advantage of being easily constructed and not liable to be broken.-The other papers, which contained but little of general interest, were entitled "On the behaviour of acetamide with sodium alcohol," by W. N. Hartley; "On iodine monochloride," by J. B. Hannay; "On tiferrous phosphide," by Dr. R. Schenk; and "On sulphur bromide," by J. B. Hannay.

Anthropological Institute, June 3.-Prof. Busk, F.R.S., president, in the chair.-The president exhibited and described a new apparatus for measuring, with ease and accuracy, the cubic capacity of skuils. Prof. Rolleston, while approving generally the method of Prof. Busk, differed with him in the nature of the material to be employed; he thought that sand was objectionable as being subject to hygrometric variation ffom which rape-seed was entirely free.-Prof. Robinson exhibited a remarkable bronze sword found in the bed of the Charwell,

"

Oxfordshire, a bronze spear from Speen, near Newbury, and other implements of bronze and stone. The president exhibited a series of stone implements from the Island of St. Vincent, West Indies, and Mr. A. W. Franks exhibited a bow and poisoned arrows lately used by the Modoc Indians, and found in Captain Jack's stronghold in the lava beds of Siskiyon County, California-The Rev. Dunbar I. Heath contributed Notes on a Mural Inscription, in large Samaritan characters, from Gaza, and claimed for it a higher antiquity than the date of the Moabite Stone.-Mr. H. Howorth read a paper entitled, "Strictures on Darwinism, part II., the Extinction of Types." The substitution of species involved two factors; Ist, the extinction of certain types; 2nd, the introduction of certain others. The paper dealt with the former factor only. PreDarwinian naturalists, and some of those who now oppose Darwin, have agreed that species become extinct through the operation of causes, such as climatic change, &c., acting ab extra and operating upon whole classes at once from without. Darwin has argued, on the other hand, that this extinction has arisen from the mutual struggles of individuals by which a certain strong and vigorous type has been evolved, and a certain weak and decrepit type extinguished; the difference between the two theories being that one relies upon external, the other upon internal causes for the explanation of the extinction of certain types. In the present paper the author examined the problem and attempted to show that the old view was the correct one. The paper passed in review the various elements that have gone to destroy types of life, changes in physical geography, changes in climate, epidemics, &c., and showed how the evidence of all of these supported the old view that extinction of type is the result of external influences, and not, as Mr. Darwin contends, of an internal struggle for existence. Frof Rolleston, Mr. Boyd Dawkins, and the president, combated the criticisms of the author.

Mr.

Royal Microscopical Society, June 4.-Chas. Brooke, F.R.S., president, in the chair. The secretary read a paper by Mr. F. Kitton, of Norwich, descriptive of a new species of Navicula, with remarks on Aulacodiscus formosus, Omphalopelta versicolor, &c., collected in Peru by Captain Perry, of Liverpool; the paper was ill strated by specimens exhibited in the room. -A paper was also read by Mr. J. Stephenson, on the appearances of the inner and outer layers of Coscinodiscus when examined in bisulphide of carbon and in air, in which the author pointed out the different effects obtained by mounting the diatoms in media of different refrangibility, and showed the value of such comparisons in determining the nature of the markings, as well as the general structure. The paper was illustrated by a number of very carefully executed drawings by Mr. Charles Stewart, and by specimens exhibited under the microscope. The meetings of the society were adjourned until October.

BERLIN

German Chemical Society, May 26.-A. W. Hofmann in the chair. Dr. Seligsohn investigating the origin of the oxalates deposited in the human body, has found that oxamide can be transformed into urea by ozone, and thinks therefore that oxamide is an intermediate product of digestion between the higher compounds of carbon and urea.--Dr. Rüdorff has found that saturated solutions of chloride of ammonium and nitrate of potassium are not influenced in their composition by adding either of these salts, while saturated solutions of nitrate of ammonium and chloride of potassium are changed in their composition by adding either one or the other to these solutions. In the same way behave most salts, so that the solution of one couple is influenced, while the other couple remains unchanged. But when K,SO, and NH, NO, are dissolved to saturation, this solution is influenced in the way described, and solutions of the opposite couple show likewise the alteration mentioned. These changes were proved by analyses and by determination of the changes of temperatures occurring. Self-evident conclusions offer with regard to the old question, if two salts in solution represent two or four different compounds.-C. Bulk spoke on the manufacture of arsenic acid from fuchsine-residues; by sublimation, as used in Elberfeld. The same chemist described a simple apparatus replacing spring-clamps in volumetric analysis. It consists of a piece of glass-rod inserted into

an

indiarubber tube. By pressing it cautiously drop after drop can be let out of the burette.-J. Grosshaus continued his speculation on the nature of chemical elements.-H. Vogel denied the existence of what Becquerel called

"rayons continuateurs." He explains the fact that photographic negatives, exposed for a few seconds to chemical light, and then to the red and yellow part of the spectrum, are acted upon by these rays, by admitting that during the first exposure chloride of silver is reduced only to the state of sub-chloride, which in its turn is acted upon by yellow light, and thus reduced to the metallic state. This explanation appears the more probable, as iodide and bromide of silver do not exhibit the same property, iodine and bromine forming but one compound with silver. Julius Thomsen reported on the amount of heat yielded by mixing nitric acid and water. The result of his experiments he sums up as follows:- A diluted nitric or sulphuric acid, when further diluted with the same quantity of water it already contains, will yield the smallest amount of heat, when the molecular heat of the acid is equal to that of the water which is contained in it.- Henry Armstrong sent a summary of his researches on isomeric derivatives of phenole, most of which are familiar to the English public.-Heinrich Baumhauer published some remarks on the natural system of chemical elements, and the relations between atomic and specific weights.F. Birlstein and A. Kullberg have found that a-dinitro-naphthaline treated with a mixture of nitric and sulphuric acids yields a new y-trinitro-naphthaline fusing at 147, while fuming nitric acid produces only the ordinary a-trinitro-naphthaline.-E. Mulder obtained a yellow solid combination by precipitating cyanamide with nitrate of silver. Its composition, CN,Age, leads the author to suppose cyanamide to be constituted according to the formula C(NH), of carbodiimide.-R. Siemens sub. mitted sulfo-acetic acid to the action of perchloride of phosphorus in order to investigate the chloride thus obtained as well as its CHCI = SOCI

reduction. To the former he gives the formula |

COCI

acid, and the sulphate, if present, remains insoluble.—On the action of nitric acid on plumbic chromate, by the same author.On a base isomeric with piperidin, and on the nitrated derivatives of the hydrocarbons of the formula C,mHm, by M. H. Gal. On the molecular rotation of gases, by M. Hinrichs.Experimental researches on the pathogeny of infarctus, &c., by M. V. Feltz.-Observations on a recent note, by M. Rabuteau, relative to the toxic properties of the iodides of tetramethylammonium and tetramylammonium, by Messrs. A. Brown and Th. Fraser.-General results of the analysis of the Geyser springs of the island of San Miguel, Azores, by M. Fouqué. During the meeting an election to the place in the Mechanical section left vacant by the decease of M. Ch. Dupin, was held with the following results:-M. Resal, 31 votes; M. Bresse, 17; M. Boussinesq, 3; M. Haton de la Goupillière and M. Maurice Lévy, I each. M. Resal was accordingly declared duly elected.

DIARY

THURSDAY, JUNE 12.

ROYAL SOCIETY, at 4.—Election of Fellows.
SOCIETY OF ANTIQUARIES, at 8.30.-What Parts of Lincoln Cathedral are
really of the Time of St. Hugh of Grenoble, A.D. 1192-1200? J. H.
Parker, C. B.

MATHEMATICAL SOCIETY, at 8-Some general Theorems relating to Vibra-
tions: Hon. J. W. Strutt.-Invariant conditions of three and four con-
currence of three Conics: J. J. Walker.-Locus of the point of concours:
of tangents to an epicycloid inclined to each other at a constant angle:
Prof. Wolstenholme.
FRIDAY, JUNE 13.

ASTRONOMICAL SOCIETY, at 8.
QUEKETT CLUB, at 8.

HORTICULTURAL SOCIETY, at 3.-Lecture.

SOCIETY OF ARTS, at 12.-Purchase of Railways by the State: Wm. Galt.
SATURDAY, JUNE 14.
ROYAL BOTANIC SOCIETY, at 3 45.

The

Academy of Sciences, June 2.-M. de Quatrefages, president, in the chair.-The president announced the death of M. de Verneuil, membre libre, which occurred at Paris, May 29. -M. de Chevreul communicated the principal results of his researches on avic acid, which will shortly be published. president presented the first part of the work on the crania of the human race upon which he and Dr. Hamy are engaged.-Tne following papers were read :- Note accompanying the presentation of a work on cellular anatomy and physiology, by M. Ch. Robin. On the transit of Venus in 1882, by M. Puiseux.-Trial, during an eclipse of the sun, of the new spectroscopic method proposed for the observation of the next transit of Venus by Father Secchi. The method consists in placing a direct-vision system of prisms before the slit of the spectroscope, and then observing the interruption of the chromosphere by the dark body. The author compares observations by his method with those of Prof. Respighi, published in the Gazetta Officiale, No. 145. Respighi saw the approach of the moon 219 secs, before Secchi, but Secchi saw the last contact 12.3 secs. before Respighi. The Rev. Father therefore suggests the use of the ordinary method (that used by Respighi) for first contact, and of his own for last. -A study of the action of the principal derivatives of amylic alcohol on polarised light, by MM. Pierre and Puchot.-Development of the freshwater algae of the genus Batrachospermum, alternate generation; second note, by M. Sirodot.-On the nature and treatment of ear tumors (orcillons), by M. Bouchut.-On Iylodes martinicencis, by M. A. Bavay.-Documents relating to the short-period Comet II, 1867, by Mr. Hind, M. Stephan, MM. Paul and Prosper Henry, M. André, and M. Baillaud. Communicated by M. Le Verrier.Discovery of a new small planet by Mr. J. Henry, at Washington, U.S.A. Displacement of a body subjected

to four conditions, by M. Ribaucour.-On the action of the electric fluid on flames, liquids, and powders, second note, by M. Neyreneuf.-On the detection and estimation of plumbic sulphate in the lead chromates of commerce, by M. Duvillier. The author adds nitric acid and alcohol, the chromate is then r.duced, the lead and cromic oxide are dissolved by the nitric

MONDAY, JUNE 16.

TUESDAY, JUNE 17.

ANTHROPOLOGICAL INSTITUTE, at 8.-The Ainos: Lieut. S. C. Holland,
R.N.-Account of an Interview with a Tribe of Bushmans in South Africa:
G. W. Stow.-Specimens of Native Australian Languages: Andrew
Mackenzie.

ZOOLOGICAL SOCIETY, at 8. 30-On the Osteology of the Maltese fossil
Elephants: Dr. A. Leith Adams, F.R.S-On the Geographica! Distribu-
tion of Asiatic Birds: H. J. Elwes.
STATISTICAL SOCIETY, at 7.45.

WEDNESDAY, JUNE 18.
METEOROLOGICAL SOCIETY, at 7.-On some Results of Temperature Obser-
vations at Durham: John J. Plummer.-On the Meteorology of New
Zealand, 1872: C. R. Marten.-On the Climate of Vancouver Island:
Robert H. Scott, F. R.S.-Meteorological Observations at Zi-Ka-Wei,
near Shanghai: Rev. A. M. Colombel and Rev. S. J. Perry.-Notes on the
Connection between Colliery Explosions and Weather: R. H. Scott,
F.R.S., and Wm. Galloway.-Annual General Meeting.
HORTICULTURAL SOCIETY.-Exhibition.
THURSDAY, JUNE 19.

ROYAL SOCIETY, at 8.30. SOCIETY OF ANTIQUARIES, at 8.30. LINNEAN SOCIETY, at 8. CHEMICAL SOCIETY, at 8.-On the Influence of Pressure upcn Fermentation. Part II.: Horace Brown.-Researches on the Action of the CopperZinc Couple on Organic Bodies, III., and on Normal and Iso-Propyl Iodides: Dr. J. H. Gladstone and A. Tribe.-On Cymenes from different sources optically considered: Dr. J. H. Gladstone.-On the Action of Bromine on Alizarine: W. H. Perkin-On some Decompositions and Oxidation Products of Morphine and Codeine Derivatives: G. L. Mayer and Dr. C R. A. Wright.-On the Decomposition of Tricalcic Phosphate by Water: R. Warrington.-On a new Tellurium Mineral, with Notes on a Systematic Mineralogical Nomenclature: J. B. Hannay.-Communications from the Laboratory of the London Institution, No. XII;-On New Derivatives of Cresol: Dr. H. E. Armstrong and C. L. Field.