those of the Pennine chain. Probably from Petchora Land to Spitzbergen was once continuous land. Sir Roderick Murchison had proved the existence of carboniferous rocks in Petchora Land and the Ural chain, but until he himself examined the specimens from Novaya Zemlya, they were not known to exist in that island. Since Sir George Nares returned, the complete flora of those parts had been described; but unfortunately nothing had been done on the northern coast of Greenland to the eastward, and an exploration of that district and of Franz-Josef Land would give clearer information as to the geological history of the Polar regions, which he felt certain were largely composed of carboniferous rocks. By placing the several acquisitions together and comparing notes on the Ural chain, Petchora Land, Novaya Zemlya, Franz-Josef Land, and Spitzbergen, a complete history could be obtained of those rocks which stretched away to the north of Asia and America."

* * *

"The great bulk of the collection brought home by Sir George Nares was carboniferous, but the coal found was of Miocene age and thirty feet thick. No one could doubt this if he knew the plants contained in the shales, &c." * "In the whole region examined by Sir George Nares, none of the carboniferous corals discovered could have lived in water less than 77°, 78° or 80° of temperature, so that most of the rocks of which the Polar regions were composed must have been formed in tropical seas. It was well known that large Enaliosaurian reptiles (Ichthyosauri) had been found in Spitzbergen. There were other things brought back by Mr. Leigh Smith, which he (Mr. Etheridge) could not yet make out, but they appeared to him to be older still. With regard to the great lava flows, they appeared to be nine in succession, most likely occurring about the same time as that of the Giant's Causeway, in Ireland, in the Miocene period, or at about the same age as the thick bed of coal found in Smith Sound. These lava flows are perfectly horizontal for many miles, showing that their condition now was just as formerly."

THE THIRD INTERNATIONAL GEOGRAPHICAL CONGRESS. - We have received the programme of the next meeting of the Congress, to be held at Venice on September 15th of this year, and to continue to the 22d. There are three classes of members: subscribers paying fifteen francs, donors giving not less than forty francs, and honorary members nominated by the committee of arrangements. The sections of the Congress are: 1. Mathematical geography, geodesy and topography. II. Hydrography. III. Physical, geological, meteorological, botanical and zoological geography. IV. Anthropological, ethnological and philological geography. v. Historical geography. vi. Economical, commercial and statistical geography. VII. The study, teaching and diffusion of geography. VIII. Explorations and travels.

Any language can be used by the speakers. Representatives

are invited from all geographical societies. Delegates will represent different departments of the Italian Government, and it is desired that commissioners should be appointed by the Governments of other countries. Geographical societies are invited to send in suggestions of questions to be discussed.

In connection with the Congress there will be held an International Geographical Exhibition to be open during the month of September. It is divided into sections corresponding to those of the Congress as follows:

Class 1.—Instruments of practical geometry. Apparatus and instruments of topography, geodesy and astronomy. Telemeters, and instruments for measuring velocity. Tables of projection and calculation. Maps exhibiting the various systems of projections. Sidereal maps; maps of triangulation and hypsometry. Original topographical charts. Publications relating to the measurement of the earth. Photographical apparatus.

Class II.-Instruments, portable and of precision, relating to hydrography. Reflectors. Chronometers, marine and pocket. Logs, leads, dredges; apparatus for deep sea sounding; thermometers for measuring the temperature at different depths; instruments for measuring tides and currents; compasses and other nautical instruments (instruments for reduction, parallel and other rulers, &c.).

Marine charts, general, coasting and special; plans of harbors and anchorages. Views of coasts. Maps of currents, winds and tides. Tables and Ephemerides for the use of astronomers and mariners. Publications relating to hydrography and maritime geography. Guides to navigation; catalogues of lighthouses, beacons, &c. Proposals for a uniform international system of buoys and beacons, and for completing the lighting of the coasts. Laying of submarine lines of telegraph.

Class III-Instruments for observing meteorological phenomena. Maps, atlases, globes representing facts relating to the dominion of physical geography and meteorology. Magnetical charts (isoclinous, isogonous and isodynamic). Charts of isobars and isotherms, &c. Maps of geological, zoological and botanical geography. Other publications and collections relative to this branch.

Class IV.-Maps and atlases referring to general anthropology, ethnology and comparative philology. Other publications and collections relating to these subjects. Grammars and vocabularies of languages little known; comparative studies.

Class v.-Maps and other publications of historical geography. Ancient and modern works and manuscripts relating to the history of geography. Ancient maps and globes. Instruments used by ancient geographers, astrolabes, &c.

Class VI.-Works, charts and diagrams of statistical, economic and commercial geography (population, agriculture, manufactures, commerce, public works, colonization, &c.). Collections of commercial products and objects made from a geographical point of view.

Class. VII.-Treatises and methods for instruction in geography. Outlines and landscapes. Wall maps; models and instruments for instructions in geography. Atlases and geographical dictionaries. Charts and maps of the globe, terrestrial and celestial globes. Copies of topographical charts; maps and plans in relief. Different methods of reproducing maps (photography, heliotyphy, lithography, zincography, photolithography, chromolithography, &c.). Materials and apparatus specially used in the preparation of maps.

Class viii.-Instruments for expeditions, astronomical determinations and topographical copies; traveling barometers and thermometers, pedometers, sextants, &c. Portable photographic apparatus, specimens of camera lucida. Route maps; sketch maps. Essays, fac-similies, reproductions and collections of every description which illustrate voyages of discovery, photographic views and drawings of countries little explored Instructions for geographical expeditions. Instruments and equipment of a traveler; portable arms, utensils, tents and medicines; portable boats; water. proof coverings and clothing; apparatus for giving light on nocturnal marches and encampments. Modes of packing and carrying on voyages of discovery. Narratives and publications of all kinds relating to geographical voyages. Publications and instruments used in Alpine climbing.

MICROSCOPY.

TEST OBJECTS. AMPLIFIER.-Why I think little of the Podura as a test, is, that it requires a skilled microscopist to appreciate it for that purpose, and a skilled microscopist can judge of the value of a lens by its performance on any object. Test-objects are of most use to a beginner, and if he does not know exactly what he ought to see, a skilled showman can make them both a delusion and a snare.

I might perhaps add to the working distance question that a concave lens inserted in the body of the microscope as an amplifier, will give increased working distance to any objective, and if we have to deal with a cover just too thick to focus through without it, the insertion of the concave will enable us to focus through at once-within limits, of course. If a flint lens, it does not much interfere with definition, and is sometimes of use to overcome the difficulty.-Edwin Holmes in English Mechanic and World of Science.

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SCIENTIFIC NEWS.

Dr. James Lewis, the well-known conchologist, died of apoplexy, at his home at Mohawk, N. Y., February 23, 1881. He was born at Schuyler's lake, Otsego Co., New York, in July, 1822. He was, therefore, nearly 59 years of age at the time of his death. Like many another who has become distinguished in natural science, his earlier education was confined chiefly to the common school. At the age of twenty-four he began to read medicine, and prosecuted his studies for some three years, when he became interested in dentistry, and abandoning the broad field of general medicine, devoted himself to this special branch of medical science. For this he was eminently fitted by his great mechanical skill, and to the implements employed in his art he contributed many permanently valuable improvements. It is as a naturalist that we have to consider Dr. Lewis. He became interested in nature in his childhood, and that interest deepened with years into admiration, and admiration into love, which led him to intelligent, untiring pursuit. It was while he resided in Boston, Massachusetts, from 1849 to 1851 that he became interested in his favorite science and formed the nucleus of what was to become one of the most valuable private collections of American land and fresh-water shells extant. From that time until a year or two previous to his death, he was a most devoted student and untiring enthusiastic collector. He is widely known to the authorities in the science he cultivated by a very extensive correspondence, of which art Dr. Lewis was certainly a master. Within the scope

of his acquaintance are embraced all the living names familiar to the younger naturalists, and many others who have passed away. His published works, when the magnitude of his labors

and the opportunities they have presented are considered, have not been many, but all published possess permanent value. They date from 1854, and number some eleven titles. The first consists of notes on “Alas. (Marg) marginata," published in 1854. In 1856 he published three papers, two in the Proc. Bos. Soc. Nat. Hist. and one in the Proc. Acad. Nat. Sci., all relating to the Mollusca of the State of New York, and two of them are local lists, with notes. In 1857 he published a single paper "On Erosion of Uniones," in Proc. Bos. Soc. Nat. Hist. In 1860, two papers, one on "Colors of Unionidæ," and the other a local list, both of which appeared in the Proc. Acad. Nat. Sciences of Philadelphia. He published nothing further until 1868, when appeared a paper in the Am. Four. of Conchology, "On the Mollusks of the Mohawk valley." In 1869, in the same journal, he published a valuable paper "On the Shells of the Coosa river," Alabama. The bibliography and indices of Dr. Lea's "Synopsis of the Unionida" next engaged his attention, and they are, in great part, largely arranged by him. His last published work of value appears in the Geological Report of Alabama for 1875(?), and contains the almost complete geographical distribution, by streams, of the shells of that State. Some very suggestive remarks are likewise appended as notes to the work which he has there performed. He was also an occasional contributor to the NATURALIST. The major part of his life's work remains behind him in the form of MSS., many of which had they been published, would add largely to our knowledge of fresh-water forms. The most of these have passed into the hands of my collaborateur, Mr. A. F. Gray. The great work of Dr. Lewis was as a systematist. In this field he was an acknowledged master, and here his services were frequently required by individuals and freely given. He arranged and classified many public collections, among which were the American fresh-water shells in the Smithsonian Institution, the last critical revision of which was made by him; the collection of the Buffalo Acad. of Nat. Sci., those of Vassar College, Mount Holyoke Seminary, Wellesley and Hamilton Colleges, and the State Cabinet at Albany. The examination of these extensive collections furnished him with material for the determination of synonomy, which, had he lived to complete it, would have very greatly reduced the number of acknowledged species. In work of this character he was truly philosophic, and his opinions commanded and obtained respect. The great changes in scientific thought occasioned by the doctrines of evolution, found an ardent advocate in him, and those great principles formed the basis of all his later work. He has often remarked, and repeated it to others in his correspondence, that the great work of the future would be done from this standpoint, and "much remains to be done in eradicating the errors of the older naturalists." He was a conscientious worker, an acute thinker, and a man of great research. In the prosecution of his studies he was

indefatigable, and here was the cause of his disease-a nervous disorder which reached its climax in his death. He lived but five hours after the apoplectic stroke, and died without regaining consciousness. His merits were recognized by various scientific societies in electing him to a membership, among which were the Philadelphia Academy, the Boston Society Nat. Hist., the American Association for the Advancement of Science and the Buffalo Academy. To the publications of all these he was a contributor. In his death science loses a man of no ostentation, but of patient and painstaking endeavor; in manner he was reserved at times, but always gentlemanly and courteous; he was single in his purpose, and devoted in pursuit of his objects. It is with a deep sense of personal loss that these lines are penned in memory of one who was universally kind and helpful; a kindness and helpfulness that many another has shared time and again at the hands. of Dr. Lewis; advice was always freely given, nor was aid ever denied when aid was needed. His death is a loss to American science that all will deplore.-R. E. C.

-The working naturalists of Des Moines have recently organized as a working body, adopting as the style of the organization, "The Agassiz Field Club," the leading idea of which is therein set forth. Articles of incorporation were filed in the latter part of April. The club is composed of specialists in various branches of natural science, and limits the membership to twentyfive, some extended acquaintance with some branch or another being a necessary antecedent to an election. Three directors were chosen, Messrs J. A. Jackson, Professor L. B. Cary and Wallace Bailey. At the formal organization, Rev. Dr. C. A. Pomeroy was chosen president, and Professor R. Ellsworth Call, corresponding and recording secretary. The club will publish any results reached which may prove of sufficient value, in the form of occasional Bulletins. It proposes, ultimately, to work up the natural history of the entire State-a thing long and sadly needed. Aside from occasional local contributions, made by individuals and at little expense save to themselves, nothing has been done in this State, and the field is open still to investigation. Dr. Parry has alone done much in its botany, Mr. J. A. Allen in its ornithology and mammalogy, and there the natural history work ends. Twice has the General Assembly instituted a geological survey, and as often brought them to an abrupt ending. The survey of Professor James Hall, from 1855-1860, resulted in the gathering of a vast amount of material which has never been in full worked up and described.1 The General Assembly, after receiving and distributing the volumes published in 1858, containing a partial account of the material obtained, and with the evidence of progress before them in a printed supplement, with maps, sections,

'Dr. Hall has since described and illustrated a large number of these forms in the Annual Reports N. Y. State Cabinet of Natural History. But there are now many of them, rare and costly, and beyond the reach of the student.-R. E. C.