As the iridium does not rust, its advantage over steel plates is obvious. The composition of the bath has not yet been announced.

-Lewis Boss of Dudley observatory, Miles Rock of the national observatory at Washington, and Charles S. Cudlip, photographer, who were sent by the U. S. transit of Venus commission to Santiago, Chili, have just returned home by way of Panama. They had a very clear day, and obtained good observations of all four contacts, and a complete set of photographs (204). Boss observed with a 5-in. Clark refractor, power 200; Rock, with a 3-in. Clark refractor, power 200; and the photographs were taken with a horizontal photoheliograph, of 40 feet focal length, forming an image on the photograph-plate about four and one-half inches in diameter. In the contact observations the images were almost steady, the definition sharp, and no atmospheric and other phenomena like black drop, etc., were observed, but simple geometrical contacts. The narrow ribbon of twilight around Venus was very silvery, and might be mistaken by inexperienced observers for direct sunlight. This twilight ribbon entirely surrounded Venus more than three minutes before second and after third contact.

– The annual meeting of the trustees of the Peabody museum of American archaeology and ethnology, at Cambridge, was held on the 17th inst., under the chairmanship of the Hon. R. C. Winthrop. The treasurer announced that he had received $900 from subscribers in aid of American research, in addition to the $2,550 mentioned in the last annual report; and the curator was authorized to expend the same for the continuation of explorations under his direction. The curator, in presenting his report, stated that he had also received $775 for special purposes, of which $550 were for Miss Fletcher's researches among the Indians. Twenty-five free lectures were given at the museum during the past year. Numerous gifts were made to the library, and the additions to the museum had been larger than in any preceding year; the large increase being chiefly due to the special explorations made either by the curator or under his immediate direction through the liberality of patrons of American research. The great importance of systematic explorations was insisted upon; and the curator showed, by his résumé of what the limited expenditure had permitted, what might be done were the museum provided with sufficient means for more extended work. He also called attention to the necessity of prompt action on the part of those who were willing to aid the museum in its work if thorough and systematic explorations were to be made in our country; as every year hundreds of mounds, earth-works, and ancient burial-places were destroyed. In concluding his report, he expressed the hope that some liberal patron of science would provide for an increase of the regular income of the

museum; and also for an addition to the building, since the present accommodations would not permit of the exhibition of more than two-thirds of the collections.

-'Parish botany' was the subject of a lecture which Dr. G. L. Goodale gave last Wednesday evening before the Divinity school at Cambridge, being one of a course addressed to students of theology by officers of other departments of Harvard university. 'The boundary-line between science and religion' was the topic discussed by Prof. John Trowbridge a fortnight ago.

- On the 8th of January was held the first meeting of the Colorado scientific society, an association organized for the promotion of scientific intercourse, observation, and record, in the State of Colorado. Its officers for the first year are S. F. Emmons, president; Richard Pearce, vice-president; Whitman Cross, secretary and treasurer; Richard Pearce, Hermann Beeger, A. Eilers, and W. F. Hillebrand, standing committee. The especial attention of the members will be devoted to geology, mineralogy, and chemistry, and their application to the industrial arts. The society certainly has in Colorado a most interesting field for investigation.

-At the meeting of the Biological society of Washington, Dec. 22, Prof. C. V. Riley pointed out the real nature of the so-called 'lignified snake of Brazil,' found beneath the bark of a tree: it is, in brief, probably nothing but the excrementitious filling of the burrow of a beetle larva, one of the Buprestidae. The head of the supposed serpent is a knot, which has been manipulated to increase the deception its natural form would give; and the tapering and tortuous form of the burrow would be impossible in a snake. Mr. Riley invites the owner to submit his specimen to a crucial test- dissection. Of course the owner declined: his idol would then have perished.

-Capt. Abney has lately delivered four very interesting lectures on recent advances in photography, before the London society of arts. The text is given in full in the last few numbers of the British journal of photography; but an excellent résumé may be found in the Popular science monthly for January, 1883.

A pharmaceutical journal in the German language has just been started in New York by Dr. F. Hoffmann, analyst to the State board of health. It is to be published monthly; and the January number, which has just reached us, contains original papers on Rhus cotinoïdes, by Prof. K. Mohr; on The position of pharmacy in regard to mysterious remedies in North America, by Prof. Dr. Maisch; a Report of the changes of the state of the pharmacopeia, by Dr. A. Tscheppe, besides two unsigned articles. Eight pages are given up to a monthly classified rundschau of pharmacy, excellently done.

- Dr. S. M. Burnett spoke at the meeting of the Washington philosophical society, Jan. 13, on Refraction in the principal meridian of a triaxial ellipsoid; regular astigmatism and cylindrical lenses; and was followed by Prof. William Harkness on the Monochromatic aberration of the human eye in aphakia. Jan. 27, Mr. H. H. Bates read a paper on the Nature of matter.

-At a meeting of the section of mechanics and engineering of the Ohio mechanics' institute, Jan. 23, papers were presented on Governors and fly-wheels, by Mr. James B. Stanwood; The wastage of water, by Mr. Thomas J. Bell; Saving of fuel, and smokeprevention, by Mr. J. P. Kilbreth. A report on Pumping-engines for public water-supply was presented by John W. Hill, M.E.; and Prof. R. B. Warder made some remarks on The duty of steamengines.

-At the Philosophical society of Washington, Feb. 10, Dr. A. F. A. King read a paper on the 'Prevention of malarial diseases, illustrating, inter alia, the conservative function of ague.' Mr. E. J. Farquhar and Dr. J. S. Billings took exception to the theories advanced. Capt. C. E. Dutton exhibited a series of oil-paintings illustrative of the volcanic phenomena of the Hawaiian islands.

- At the meeting of the American academy of arts and sciences, Feb. 14, the following papers were presented: Quantitative researches in photography, by Mr. W. H. Pickering; Photography as a means of determining the light and color of the stars, by Messrs. E. C. and W. H. Pickering; The historical hydrography of the west coast of North America, by Mr. J. Winsor.

-At the meeting of the Biological society of Washington, Feb. 16, Dr. Coues' paper on zoological nomenclature applied to histology was discussed, and papers were read on Biology and classification, by Mr. Newton P. Scudder; On the structures of protoplasm and karyokinesis, by Mr. John S. Ryder; The human fauna of the District of Columbia, by Prof. Otis T. Mason; Section cutting and mounting of hard woods, with illustrations, by Dr. Thomas Taylor.

26, before the students of the latter institution. The gesture-language was delivered with remarkable ease and grace. The audience was very attentive throughout the lecture, and showed its appreciation of the points made by the speaker, by nods and movements of the fingers.

We learn from the daily papers, that a proposition to abolish the geographical survey of New Jersey is meeting with favor on the part of some would-be economists in the legislature of that state. Apart entirely from its scientific worth, it would be hard to point out a state in the Union where the quiet inexpensive work of the state geologist has been so fruitful in economical value as here.

A course of ten lectures on zoology is being given by Prof. A. S. Bickmore in the American museum of natural history, Central Park, New York, on Saturday mornings. The lectures commenced on Jan. 20, and are almost wholly upon the higher vertebrates, those in March being upon monkeys and the different races of men. We understand the course is very well attended; but the small lecture-room is a disgrace to such an institution if it contemplated such courses at the outset.

- In recognition of their scientific services at the international geological congress held last year at Bologna, the Italian government has created Prof. James Hall of Albany a Commander of the ancient order of Sts. Mauritius and Lazarus, and given Dr. T. Sterry Hunt of Montreal the rank and decoration of Officer of the same order.

-The first half of the second course of scientific lectures delivered in the National museum, under the auspices of the biplogical and anthropological societies of Washington, now completed, has met with the most remarkable and flattering success. The audiences increased in size from the first; the number of persons attending lectures far exceeding the seatingcapacity of the hall, and in one instance exceeding two thousand. The first lecture by Capt. Clarence E. Dutton, on Rivers, although brief and not illustrated, contained a clear, and in many respects original, exposition of the rôle of rivers in the great drama of the globe. Prof. Otis T. Mason, who delivered the second lecture on the 20th ult., took for his topic The races of men, and gave a brief but succinct summary of the present condition of knowledge in this branch of anthropology. The lecture was illustrated by busts and casts of different races of men, from the museum collection, and by diagrams. Mr. George Kennan, who was third in the course, delivered an eloquent lecture on the Mountains and mountaineers of the Caucasus, and was listened to with closest attention during the two hours occupied in its delivery. Dr. D. W. Prentiss happily selected for his theme, Mesmerism in animals, -a topic which, although attracting much attention among French savants, is familiar to the

American public almost exclusively through the insufficient medium of the newspapers. Dr. Theo. Gill, who lectured on the 10th inst. on Mythical animals, departed from the consideration of animals which exist in fact, and gave his audience an account of some which exist in fancy. Dr. John S. Billings closed the first half of the course, taking for his theme, Germs and epidemics. He gave a concise account of the results of the latest investigations of Pasteur and others, regarding the relations of microscopic organisms to disease; weaving in, to a greater or less extent, his own views upon the matter.

The programme for the second half of the course is as follows: Feb. 24, Prof. L. F. Ward, the Plant life of the globe, past and present; March 3, Mr. W. H. Dall, Pearls and pearl-fisheries; March 10, Major J. W. Powell, Indian mythology; March 17, Prof. C. V. Riley, Adaptation and interdependence between plants and insects; March 24, Prof. C. A. White, the Teachings of paleontology; March 31, Dr. R. Fletcher, U. S. A., Human proportion in art and anthropometry.

RECENT BOOKS AND PAMPHLETS.

[Continuations and brief papers extracted from serial literature without repagination are not included in this list. Excep tions are made for annual reports of American institutions, newly established periodicals, and memoirs of considerable extent.]

Baltimore-Johns Hopkins university. Studies in historical and political science; ed. by Herbert B. Adams. Baltimore, University. 1882-83. 8°.

I. An introduction to American institutional history; by Edward A. Freeman. 1882. p. 39.

II. The Germanic origin of New England towns; by H. B. Adams. With notes on cooperation in university work. 1882. p. 57.

III. Local government in Illinois; by Albert Shaw: Local government in Pennsylvania; by E. R. L. Gould. Jan., 1883. p. 37. IV. Saxon tithing-men in America; by H. B. Adams. Feb., 1883. p. 23.

Bible myths, and their parallels in other religions; being a comparison of the old and new testament myths and miracles with those of heathen nations of antiquity, considering also their origin and meaning. N. Y., Bouton. 1883. 650 p. 8°.

Bouchon-Brandely. Rapport au ministre de la marine sur la génération et la fécondation artificielle des huîtres portugaises. Paris, 1882. 51 p. 8°.

Brubaker, A. P. Physiology. Philad., Blakiston. 1883. 133 p. 12°.

Buet, Charles. Madagascar, la histoire, moeurs, religion, flore, etc. 391 p. 8°.

reine des îles africaines: Paris, Palmé. 1883. 12+

Cambridge entomological club. Annual reports for 1882. Cambridge, Club. 1883. 31 p. 32°.

Annual

Connecticut agricultural experiment station. report for 1882. New Haven, State. 1883. 114 p. 8°. Conn.-Shell fish commissioners. Second report. Middletown, State. 1883. 44 p., map. 8°.

Davy, Humphry. Les derniers jours d'un philosophe. Entretiens sur la nature, les sciences, les métamorphoses de la terre et du ciel, l'humanite, l'âme, et la vie eternelle. Ouvrage traduit de l'anglais, accompagné d'une préface et de notes, par C. Flammarion. 9e éd. Paris, Didier. 1882. 32+374 p. 18°.

Fabre, J. Henri. Histoire naturelle. Géologie (programme officiel du 3 août 1880 et instructions ministérielles du 18 oct. 1881). 3e ann. Paris, Delagrave. 1882. 260 p. 12°.

Ferris, B. G. A new theory of the origin of species. N. Y., Fowler and Wells. 1883. 278 p. 12.

Gerhard, W. Paul. House drainage and sanitary plumb. ing. N. Y., Van Nostrand. 1882. 205 p. 24°.

élémentaire appliquée aux Chimie organique. Paris,

Girardin, J. Leçons de chimie arts industriels. 6e éd. Tom. iii. Masson. 1883. 620 p., 330 fig. 8°. Grand, S. L'industrie huitrière à Marennes; la Seudre et ses rivages; des claires à verdir, soins annuels à donner aux claires, etc. Paris, Michelet. 1883. 31 p. 8°.

Guérin, Victor. Rapports addressés à M. le ministre de l'instruction publique, sur sa mission scientifique dans le Liban. Paris, imp. Levé. 1883. 28 p. 8°.

Hale, P. M. The woods and timbers of North Carolina; a compilation from the botanical and geological reports of Drs. Curtis, Emmons, and Kerr; to which are added information obtained from the census bureau and accurate reports from the several counties. Raleigh, Hale. 1883. 272 p., map. 12°.

Indiana. Department of geology and natural history. Eleventh annual report, 1881. John Collett, state geologist. Indianapolis, State. 1882. 414 p., 5 maps, 55 pl. 8°.

Kuhff, G. A. Les organes génitaux de l'homme et de la femme, structure et fonctions, etc. 2e éd. Paris, Ballière. 1883. 64 p. 8°.

Latteux, Paul. Manuel de technique microscopique, ou Guide pratique pour l'étude et le maniement du microscope. 2e éd. Paris, Delahaye, etc. 1883. 11+477 p., 177 fig. 18°. Lecouteux, Edouard. Le blé, sa culture intensive et extensive. Paris, imp. Chaix. 1882. 8+413 p., 60 fig. 18°.

Marchand, Léon. Botanique cryptogamique pharmacomédicale; programme raisonné d'un cours professé à l'école supérieure de pharmacie de Paris. Tom. i. Paris, Doin. 1883. 481 p. 8°.

Milne-Edwards, Alphonse. Anatomie et physiologie animales. Paris, Masson. 1883. 4+406 p. 311 fig. 18°.

Mortillet, Gabriel de. Le préhistorique: antiquité de l'homme (Bibl. sciences contemp.). Paris, Reinwald. 642 p. 8°.

New York.-Linnaean society. Transactions. N.Y., Society. 1882. 168 p., portr. 1. 8°.

1883.

Vol. i.

Niox, Comm. Géographie militaire. v. Europe orientale et bassin de la Méditerranée. le partie: péninsule des Balkans. Paris, Baudoin. 1882. 8+231 p. 18°.

O'Donovan, E. The Merv oasis. Travels and adventures east of the Caspian during 1879-81, including five months' resi dence among the Tekkés of Merv. 2 vol. N.Y. 1883. illustr. 8°. Pharmaceutische rundschau und zeitung für die wissenschaftlichen gewerblichen interessen der pharmacie und verwandten berufs- und geschäftszweige in den Vereinigten Staaten; herausg. von Dr. Fr. Hoffmann. Bd. i. no. i. N. Y. 1883. 28 P., m. 4°.

Pioger, L. M. Dieu dans ses oeuvres; les splendeurs de l'astronomie, ou Il y a d'autres mondes que le nôtre. Paris, Haton. 1883. 18°.

La lune. 4+315 p. Le soleil. 8+373 p.

Poitevin, A. Traité des impressions photographiques. Suivi d'appendices relatifs aux procédés, par M. Léon Vidal. 2e éd. Paris, Gauthier- Villars. 1883. 14+280 p., portr. 18°. Proctor, R. A. The great pyramid, observatory, tomb and temple. N.Y., Worthington. 1883. 8+323 p. illustr. 12°. Rawlinson, G. The religions of the ancient world, including Egypt, Assyria and Babylonia, Persia, India, Phoenicia, Etruria, Greece, Rome. N.Y., Scribner. 1883. 12+249 p.

illustr. 12°.

Rochas, Albert de. La science des philosophes et l'art des thaumaturges dans l'antiquité. Paris, Masson. 1883. 220 p. 24 pl. 8°.

Selvatico, Silvestro. Sur le développement embryonnaire des bombyciens. Traduction par J. Pelletan. Paris, Doin. 1883. 31 p., 7 pl. 8°.

Tissandier, Gaston. Les martyrs de la science. 2e éd. Paris, Dreyfous. 1883. 334 p., 34 pl. 8°.

Tyndall, J. Heat as a mode of motion. New enl. ed. N.Y., Appleton. 1883. illustr. 12°.

U.S.-Corps of engineers U.S. army. Professional papers, no. 24. Primary triangulation of the lake survey; by Lieut.Col. C. B. Comstock, U.S.A. Wash., Government. 1882. 920 p. 4°.

Waldmann, F. Der bernstein im alterthum; historischphilologische skizze. Fellin. 1883. 87 p. 4°.

Wharton, W. J. L. Hydrographical surveying; a descrip. tion of the means and methods employed in constructing marine charts. London. 1882. 8°.

Yung, Emile. Le sommeil normal et le sommeil pathologique; magnetisme animal, hypnotisme, névrose histérique. (Bibl. biol. intern.) Paris, Doin. 1883. 196 p. 18°.

FRIDAY, MARCH 2, 1883.

THE INTERNATIONAL

CONFERENCE FOR THE DETERMINATION OF THE ELECTRICAL UNITS.

Ar a meeting of the electrical congress, Oct. 5, 1881, it was recommended that the French government should invite the other powers to constitute an international commission to discuss the following points:

1. To determine for practical science the conditions which a column of mercury should fulfil in order to represent the electrical unit of resistance.

2. To determine upon a definite standard of light.

3. To arrange a systematic and universal plan for studying atmospheric electricity, terrestrial magnetism, and the exchange of international observations.

In accordance with this recommendation the French government communicated with the other powers; and representatives appointed by the various governments assembled in Paris, Oct. 16, 1882, at the residence of the foreign minister. At the first meeting there were forty-seven representatives present, among whom were Helmholtz, W. Siemens, Wiedemann, Kohlrausch, Fröhlich, Lorenz, Dumas, Mascart, Tacchini, and Weber. The representatives from Great Britain and the United States had not been notified in time to attend the opening of the conference.

the mechanical equivalent of heat. Sir W. Thomson and Helmholtz pointed out that the heat method depended upon the measurement of current, and could only be considered as a method of control. MM. Lorenz and Roiti presented papers upon the determination of the ohm, and Wiedemann gave a bibliography of the subject. After hearing the careful and minute discussion of the subject, the following resolutions were adopted :

1. The commission consider that the determinations made up to the present time are not sufficiently concordant to allow the value of the ohm to be fixed.

They believe that it is necessary to continue the researches upon this value. Although they do not advise observers to restrict themselves in the choice of methods, they consider the following methods particularly adapted for exact determinations:

a. Induction of a current upon a closed circuit (Kirchoff).

b. Induction by the earth (W. Weber). c. Decrement of moving magnets (W. Weber).

d. Apparatus of the British association.
e. Methods of M. Lorenz.

It is also desirable to determine the ohm by the quantity of heat evolved by a given current, using this method as a control method.

2. It is thought desirable that the French government should take the necessary steps to prepare certain standards of resistance, which can be placed at the disposal of scientific men, in order to compare their values.

The commission was, at first, of the opinion, that when the results of the different observers reach an approximation of 1000 of the true value, the value of the practical unit of resistance should then be fixed. After much discussion, it was felt that no decision upon the limit of accuracy could be reached at present. Mascart then described the methods adopted for the study of atmospheric electricity. Sir W. Thomson showed that it was important to make observations upon the air in a definite enclosure, or, in other words, upon the air itself. Helmholtz in this connection remarked,

that one of his students had shown that the electrification of the air in the interior of a laboratory could be readily perceived. Thomson then gave a short description of the kind of room and the disposition of its walls which would be desirable in an observatory for such researches. The commission concluded to recommend to the various governments regular observations on atmospheric electricity.

An interesting discussion upon lightningrods then followed. Helmholtz said, that statistics in regard to strokes of lightning and in regard to the effect of various kinds of lightning-rods were about to be collected in the province of Schleswig-Holstein, the position of this province between two seas being particularly advantageous. It already had appeared that the country is more exposed to strokes of lightning than the cities, and that in villages the public buildings were more frequently struck than the houses. He also remarked, that the academy of Berlin had recommended the employment on telephone-lines, where they enter houses, of a lightning-protector, consisting of two little spheres very near each other, one of which is connected to the line, and the other to the earth. M. Ludewig of Germany gave some statistics in regard to damage to telegraphic and telephonic apparatus in Germany during the period from April 1, 1881, to Aug. 20, 1881. During this time there had been 2,301 storms; and these had produced 2,165 cases of damage, more or less serious.

It was debated whether a set of questions in regard to the perturbing effect of storms upon telegraphic apparatus should be issued. After much discussion, a sub-committee was formed to formulate a set of questions. Among the members of this committee were Helmholtz and Mascart. The question of the observation of earth-currents was then taken up. It was regretted that the existing telegraph lines running north and south, and east and west, could not be utilized for the observation of earth-currents. The pressure of business usually prevented this. M. Blavier pointed out, that the earth-currents are generally too feeble to be observed on telegraph-lines which

are in operation. Moreover, the polarization of the earth-plates of the battery would cause trouble. Mascart, in reply, said that he had noticed that the maximum disturbance was reached slowly, through a period of several days, and died out also slowly. He therefore thought that existing telegraphic lines could be used, notwithstanding the objections of M. Blavier. He proposed that observations should be made upon lines reserved for the purpose, and also on existing telegraphic systems. A question arose upon the length that these lines should have. Helmholtz remarked, that one could make observations on lines from one to two kilometres in length. It would be necessary, however,, to shun the effects of polarization of the electrodes. He thought that special plates surrounded by peroxide of manganese might be serviceable.

The commission in general were in accord on the necessity of organizing a systematic study of earth-currents upon telegraphic lines, or at least records of these currents on the days specified for observations by the international polar expeditions (the first and fifteenth of each month, from September, 1882, to September, 1883). In a general discussion which followed, upon lightning-conductors and electrical storms, Helmholtz expressed his doubt about the efficacy of extent of contact of lightningconductors with the earth, and the varied nature of the plates employed. M. Van der Mensbrugghe (Belgium) spoke of the desirability of studying the nature of lightning discharges, especially that termed ball-lightning. Mascart replied, that he did not believe that cases of ball or globular lightning were well substantiated. It might happen that it was an illusion of the senses, and could therefore be relegated to physiology rather than to physics. The commission then discussed the question of studying the best conditions for the establishment of an international telemeteorographic system, which would permit various stations in different countries to communicate continuously with each other. They decided that it did not appear that the time had come for the establishment of such a system; but they ex