work. The library contains about 1,500 volumes, and it is not difficult to obtain books from elsewhere when necessary.

On the ground floor of the central portion of the building is an aquarium well stocked from the native fauna and open to the public for a small fee. Above the aquarium is the main Laboratory, a well-lighted and well-ventilated room of moderate height, 70x34. The windows, which are very large, are separated by partitions about seven feet high, forming a series of alcoves, each about ten feet square. Through the center of the Laboratory runs a continuous line of aquaria designed for experimental work. The whole place is clean, orderly and well kept (except, of course, my own alcove), and as good a place for work as could be desired. Every investigator is given a pass-key to the Laboratory, which is available for work day or night and every day precisely as one wishes or as his work requires. Smoking is allowed everywhere, which is a luxury to me, for you may remember that an occasional cigarette is necessary for my health.

The staff consists of three naturalists, including the Director, and eight employees, such as janitor, boatman, Laboratory Diener, etc. The latter is well trained in the art of preserving marine animals in the expanded condition, in the art of mixing reagents, and the like. The Laboratory is provided with a steamer about 60 feet long and with a sail-boat, both of which are kept well employed collecting for the supply department, so that there is an abundant supply of fresh material constantly brought in. In the Official Reports of the Laboratory stress is naturally laid on its needs. Some with whom I have talked have seemed to interpret these appeals as signifying extreme poverty, and are surprised accordingly to find an establishment so well equipped. It is not, of course, perfect, but, in my opinion, it is an excellent laboratory, admirably managed.

In the university vacations the place, I am told, is full of workers, but during the present winter there have been in residence only the three naturalists on the staff and three other investigators besides myself.

I have read of the severe winter at home with many chuckles of satisfaction that I am not in

it, for, as you know, I have no affection for our blizzards, and I am contented that they are unknown here. The lowest temperature recorded this winter at Plymouth was 29° F. on what the newspapers called a 'bitter cold night,' and the highest during January was 56°. As a rule, it has been 45° or thereabouts. We have a good deal of rain, but, by a fortunate meteorological arrangement, it is rarely cold and stormy at the same time. The south and southwest winds are mild and rainy and the easterly and northerly winds clear and cool. The winds are so tempered that sheep graze in the public parks all winter, while on tennis-courts, and on lawns where sheep are not allowed, lawn-mowers have been in constant use to keep the grass under control. Many of the more hardy garden plants bloom all winter, and the ivy and numerous shrubs are luxuriant with greenness. Spring is already at hand (February 17th), as is apparent from the wild violets and primroses, blossoms of which I have picked in the fields this week. One day it snowed for two hours, but at the end of that time there was no snow to be seen, every flake having melted as it fell.

Of course, the people exercise the right of all free men to grumble at the weather, but I have seen many climates which gave far more cause for grumbling. There is a widspread impression, which I suspect may be correct, that the big storms here are hatched on our side of the Atlantic and find their way across. Whenever we get a good strong southwester people say with an injured air, 'See how the Americans treat us,' almost as if there were personal spite in it. On the whole, the climate is to me infinitely more agreeable than that of New England.

To sum it all up, Plymouth and its surroundings are beautiful; the climate is (to me) agreeable; my family has been in most excellent health all winter; and, lastly, the Laboratory is a most delightful place for work.

extent. Geological literature is of too great bulk for the working geologist to attempt to ascertain whether or not names which he proposes to use have been preoccupied. To illustrate what the present system is leading to, a few instances of some prominence will be cited.

In 1883 Hague described, in a report of the U. S. Geological Survey, the Eureka quartzite, a sub-division of the Silurian, in the Eureka district, Nevada. In 1891 Simonds and Hopkins, in a report of the Arkansas Geological Survey, used the name Eureka shale for a supposed Devonian horizon; while in 1898 Haworth, in a report of the Kansas Geological Survey, proposes the name Eureka limestone as a subdivision of the Coal Measures.

In 1879 Peale, in the 11th Annual Report of the U. S. Geological and Geographical Survey of the Territories, employed the term Cache Valley Group for a sub-division of the Pleistocene of Utah. Becker described, in 1888, the Cache Lake beds of California, in Monograph XIII of the U. S. Geological Survey, and referred them to the Tertiary. In 1896 G. M. Dawson, in a report of the Canada Geological Survey, uses the name Cache Creek formation for an horizon of the Carboniferous to include strata described by Selwyn in 1872 as Upper and Lower Cache Creek beds.

In 1842-46 Emmons, Vanuxem and Mather employed, the term Erie division as a sub-division of the New York system. In the Ohio Geological Survey reports, the Erie clay was used as a sub-division of the Pleistocene, and Erie shale was referred both to the Carboniferous and Devonian. In 1875 Lesley described, in a report of the Pennsylvania Geological Survey, the Erie shale, which he referred to the Silurian. In 1898 Haworth described the Erie limestone of the Coal Measures of Kansas. The above references are given merely to illustrate the confusion that is likely to arise from use of new geographic terms if the literature is not carefully examined for previous use.

For the past eighteen months the writer has been engaged in preparing a card catalogue of geologic formation names, during such time as could be taken from other office and field work. This catalogue has already assumed considerable proportions, and is now being consulted by

*

THE BERLIN TUBERCULOSIS CONGRESS. THE German Central Committee for the erection of Sanitaria for Consumptives have issued a call for a Congress to be held in Berlin, Germany, May 24-27, 1899, for the purpose of discussing the subject of tuberculosis. The Congress will meet in the new building of the Imperial Diet and is under the patronage of Her Majesty, The Kaiserin, while Prince Hohenlohe, the Imperial Chancellor, will serve as Honorary President. All of the German States, also local authorities, medical faculties and societies, and all corporations interested in fighting tuberculosis, have been requested to send delegates, and all foreign countries represented at the Imperial Court have also been invited to take part. The United States Embassy has been requested to extend a cordial invitation to American physicians to become members of the Congress, and the same invitation has been extended through other missions to physicians of other nationalities.

As a basis for discussion papers will be presented as follows: (1) 'Distribution and extent of tuberculosis' by Geheimrath Koehler, Director of the Imperial Health Office, and Geheimrath Krieger, of Strassburg; (2) 'Etiology,' by Professors Robert Koch and B. Fraenkel, of Berlin; (3) Prophylaxis,' by Pro

*Written at the request of Dr. Pannwitz, General Secretary of the Congress, and forwarded simultaneously to several American journals. The medical, veterinarian and scientific press is requested to call the attention of its readers to this Congress.

fessor Gerhardt and Generaloberartzt Schjerning, of Berlin; (4) 'Therapy,' by Professor von Ziemssen, of Munich, and Professor Schroetter, of Vienna; (5) 'Sanitaria,' by Herr Gaebel, President of Imperial Insurance Office, Berlin, and Dr. Dettweiler, of Falkenstein.

Following the presentation of the two leading papers (limited to 20 minutes each) in the respective divisions, there will be a general discussion, speakers being limited to 10 minutes each. All papers and remarks are to be in German, although the chairman is empowered to make exceptions during the general discussion.

All persons interested in the subject of tuberculosis are eligible for membership; membership cards (20 Marks, nearly $5) are to be obtained at the office of the Congress ('Bureau des Organisations-Komites, Wilhelm Platz 2, Berlin, W') and entitle the holder to a copy of the 'Proceedings. An early registration is requested. The writer has been requested to furnish a list of Americans to whom special invitations to the Congress should be sent. He has complied with this request, so far as his personal and professional acquaintance with specialists in this line has permitted, and has also suggested to the committee that invitations be sent to the various medical societies and faculties. There are undoubtedly many American practitioners especially interested in tuberculosis and possibly some laboratory workers whom he has overlooked. Should any such person desire to attend the Congress, yet prefer to receive a personal invitation, the writer will be pleased to forward the name of such persons, upon proper introduction, to the Executive Committee of the Congress. As 'proper introduction' will be considered a letter from any recognized medical, scientific or veterinary faculty or society. CH. WARDELL STILES, PH.D., Scientific Attaché, U. S. Embassy, Berlin, Germany.

ASTRONOMICAL NOTES.

THE RUTHERFURD PHOTOGRAPHS. AMONG recent additions to the literature of the astronomy of precision are four contributions from the Observatory of Columbia University which give the results of measurements of the Rutherfurd plates. Dr. Davis contributes

three of these, entitled 'Catalogue of Sixty-five Stars Near 61 Cygni,' 'The Parallaxes of 611 and 612 Cygni,' 'Catalogue of Thirty-four Stars near Bradley 3077.' Mr. Schlesinger contributes the fourth, upon 'The Præsepe Group.' All these are most admirable illustrations of the highest type of astronomical work in the determination of exact positions of the stars, and careful deductions therefrom. No pains have been spared to make the original measures under such conditions that the instrumental constants shall be well determined, and all corrections and reductions accurately applied. The result is three catalogues of stars whose coordinates relative to the reference star in each group are determined with great precision. The two catalogues of stars near 61 Cygni and Bradley 3077 are for the purpose of discussing the parallaxes of these well-known stars. The most interesting result of Dr. Davis's discussion is the well-marked difference of parallax between 611 and 612 Cygni, determined from both position angles and distances, the numerical amount of which is 0.072 ± 0.028. This large difference, if real, explains the failure of double-star observers to detect any evidence of orbital motion, and would show that the stars do not form a binary system. A confirmation of this conclusion is found in a careful discussion of Wilsing's determinations of the distance of these two

stars, which gives 0.0876 for the difference. The mean of the different determinations of parallax for the stars made by other astronomers shows a difference of 0.082, which confirms further the reality of the result. The author urges the making of a more extended series of comparisons by photography to give further evidence on this subject.

An interesting result of Mr. Schlesinger's study of the measures of the Præsepe stars is that the method of orienting the plate by the method of trails is not as accurate as that ba ed upon assuming the coordinates of several comparison stars on the plate, as determined by the meridian circle or the heliometer. It was Mr. Rutherfurd's rule to make two impressions of the regions photographed, stopping the clock for a few seconds between them, and also to give a third impression of the brightest stars by stopping the clock about three minutes and

making a brief exposure. In this way each plate contains its own data for orientation. The author thinks that the somewhat large discrepancies between this method and that by meridian circle observations is due to the jarring of the plate by stopping and starting the clock. Its value as an independent method, however, is recognized.

THE SOLAR ECLIPSE OF MAY 28, 1900. THE Committee appointed at the recent conference of astronomers and astrophysicists to consider the observations to be made at this eclipse has issued a circular letter asking for opinions as to the observations deemed advisable and what cooperation our American astronomers can render. The eclipse path extends from the Gulf coast to the Atlantic, but the duration of totality is short, only 1m 13s near New Orleans and 1 40s near Norfolk, Va., according to the circular. The figures given by the circular of the English Nautical Almanac are a few seconds larger than these, 1m 17.8 west of New Orleans, and 1TM 45.6 south of Cape Henry, Va. Some excellent points of observation may be found in Portugal and Spain, where the totality will range from 1 348 to 1m 19s. European astronomers are likely to locate at this end of the line. American observers should cover thoroughly the path through the United States, which includes many places readily accessible. The U. S. Weather Bureau has issued a second bulletin upon the probable weather to be expected. This is based upon special reports made in May, 1898, the former report including those of 1897. A third report for 1899 is promised. The conclusion thus far is that the most unfavorable weather is to be expected on the Gulf and Atlantic coasts, and that the most favorable locations are in the northern parts of Georgia and Alabama, upon the southern end of the Appalachian Mountains. WINSLOW UPTON.

PROVIDENCE, R. I., March 15, 1899.

Dynamos and Motors' in the London Electrician of December 30, 1898, find, by means of an exploring coil and instantaneous contact maker, that the effect of commutation is to produce somewhat regularly recurring ripples in the curve connecting E. M. F. and position of the exploring coil, the maximum of the ripples occurring at intervals equal to the width of a coil, decreasing in magnitude as the distance from the commutated coil increases and nearly disappearing before the interpolar gap is passed. These ripples were found to be more marked with narrow than with wide brushes, which is explained by the damping effect of the adjacent short-circuited coils acting as secondaries to each other. The ripples are also more marked for heavy than for light currents and for motors than for dynamos.

TELEGRAPHY AND MAGNETIC INDUCTION.

He

S. EVERSHED, in an article on Telegraphy by Magnetic Induction' in the same journal, deduces a formula for the mechanical energy available in a distant secondary circuit in which no capacity is used, in terms of dimensions, resistance, frequency, etc., and from this calculates that in the case of two circuits using together 1,000 kgm. of wire, each 1,000 meters square and 10 kilometers apart, with a frequency of 100 and 100 watts in the primary, there would be available in the secondary .34 ergs. per second. Experiment shows that 2.9 X 10-6 amp. gives easily readable Morse signals in an ordinary telephone, this being double the audible current (this presumably for a frequency of 400). then finds that in the above case, but with frequency equal to 400, there is 12 X 10-6 amp., and that hence the readable signals could be produced with 250 kgm. of copper. For satisfactory audible signals the frequency must be at least as high as 400, and here the undetermined effect of absorption of these waves by the material of the earth comes in. If this proves serious it may be necessary to use lower frequencies and other forms of receivers. A receiver is described consisting of a tuned rectangle of wire, vibrating in a strong field, or, better, two rectangles vibrating synchronously, but in opposite directions. Such instruments are being used at Lavernock and Flat Holm as