NOTES. THE Royal Meteorological Society has arranged for an exhibition of meteorological apparatus to be held on March 14-17. The exhibition will be chiefly devoted to recording instruments, but it will also include new meteorological apparatus invented or first constructed since the society's last exhibition, as well as photographs, drawings, and other objects possessing meteorological interest. Science announces that Prof. Ernest Rutherford, of McGill University, has been appointed Silliman lecturer at Yale University for 1905. The previous Silliman lecturers have been Prof. J. J. Thomson and Prof. C. S. Sherrington. 24, As Prof. G. H. Bryan, F.R.S., is unable to lecture at the Royal Institution on Friday evening, March Sir Oliver Lodge, F.R.S., will deliver a discourse on that date on "A Pertinacious Current." A GRANT of gol. has been awarded by the Berlin Academy of Sciences to Prof. R. Hagenbach, of Aachen, and Dr. Konen, of Bonn, for the publication of a spectrographic atlas. THE de Candolle prize of 20l. for the best monograph on a genus or family of plants is offered by the Physical and Natural History Society of Geneva. Papers may be written in Latin, French, German, Italian, or English, and should be sent before January 15, 1906, to M. le Président de la Société de Physique et d'Histoire naturelle de Genève, l'Athénée, Genève (Suisse). Members of the society are not admitted to this competition. We are sorry to see in the Athenaeum the announcement of the death, on January 21, of Mr. E. Crossley, of Halifax, in his sixty-fourth year. Mr. Crossley published in 1879, in conjunction with Messrs. Gledhill and Wilson, a valuable" Handbook of Double Stars, which is complete in its information up to the time of publication. The Crossley reflector, with which excellent work is being done at the Lick Observatory, was presented to that observatory by Mr. Crossley, and contains one of the best mirrors made by the late Dr. Common. PROF. J. W. MASON, professor of mathematics at the College of the City of New York from 1879 to 1903, died on January 10 at the age of sixty-nine years. The death is also announced of Dr. Guido Bodlaender, professor of physical chemistry and electrotechnics at the Brunswick Technical College. WE regret to see the announcements of the deaths of Dr. T. H. Behrens, professor of microchemistry at the Delft Polytechnic School, on January 14, at the age of sixty-two; of Dr. Albert von Reinach, the eminent geologist of Frankfurt, on January 12; of Prof. Benjamin W. Frazier, professor of mineralogy and metallurgy at Lehigh University since 1871; and of M. Joseph Chaudron, the Nestor of Belgian mining engineers, at the age of eighty-two. M. Chaudron's method of boring shafts was first employed in 1848, and its most recent application is now in progress at the colliery at Dover. THE annual general meeting of the Iron and Steel Institute will be held on May 11 and 12. The annual dinner will be held-under the presidency of Mr. R. A. Hadfield-in the Grand Hall of the Hotel Cecil on May 12. The autumn meeting will be held in Sheffield on September 25-29. Members of the institute are invited to participate in an International Congress of Mining, Metal 325 lurgy, Mechanics and Applied Geology, to be held at Liége on June 26 to July 1, in connection with the International Exhibition. The general secretary of the organising committee is M. Henri Dechamps, 16 Quai de l'Université, Liége. DR. F. T. ROBERTS will deliver the Harveian Oration of the Royal College of Physicians of London on June 21. Dr. W. H. Hamer has been appointed to deliver the Milroy lectures on State medicine and public hygiene for 1906; the lectures for this year will be delivered by Dr. T. M. Legge on 'Industrial Anthrax," on March 7, 9, and 14; Dr. W. H. Allchin will deliver the Lumleian lectures, "Some Aspects of Malnutrition," on March 28, 30, and April 4; and the second Oliver-Sharpey lecture, "The Influence of Atmospheric Pressure on Man," will be delivered by Dr. L. E. Hill on April 6. Other lectures to be delivered during the year are the Croonian, by Prof. E. H. Starling, F.R.S.; the FitzPatrick, on The History lecture, by Dr. G. R. Murray. of Medicine," by Dr. Norman Moore; and the Bradshaw 66 ON Sunday, January 22, M. Victor Serrin died, at Neuilly-en-Tel, Department of Oise, aged seventy-five years. M. Serrin was the inventor of the first automatic regulator of the electric arc light used in the public service. The action is so satisfactory that the apparatus is still in use, after fifty years of scientific progress. M. Serrin produced other ingenious inventions, but no other has had the importance of his arc lamp. In 1852, M. Serrin was in charge of the rebuilding of the Pont St. Michel in Paris, and, as the work was urgent, men were kept busy night and day. At night an electric light, with hand-feed adjustment, was used, since no regulators existed. Provided with blue spectacles, Serrin watched the lamp and adjusted the carbons when necessary. He thus contracted ophthalmia, in consequence of which he nearly lost his sight. The idea of the regulator then occurred to him, and he made all the parts with his own hands. At the funeral the principal scientific societies of Paris sent wreaths. MESSRS. WINSLOW AND BELCHER have carried out an investigation on the variations in the number of bacteria in samples of sewage kept in the laboratory (Journal of Infectious Diseases, i., No. 1). They find that the total number of bacteria rises rapidly during the first twenty-four hours of storage, increasing more than ten-fold, and then decreases steadily for at least six months. The rise and fall in the number of bacteria appear to affect the various organisms in an almost equal degree, there being no tendency towards the development of a pure culture of any dominant form. 326 A THIRD example of variation-among gold and silver pheasants-is discussed by Mr. F. Finn in the Avicultural Magazine for January. These variations, in the colour and markings of the plumage, would, in the author's opinion, be regarded as at least of subspecific value if the birds were wild instead of domesticated. IN the Proceedings of the Royal Physical Society of Edinburgh for December last (vol: i. part i.) Dr. Gerald Leighton discusses the variation in the matter of scaling displayed by the common viper (Vipera berus), which he shows to be very extensive. His main thesis is apparently to demonstrate that squamation is an unsound feature to rely in the discrimination of reptilian upon which species, and consequently that the "small red viper" of the British Isles is entitled to be regarded as a distinct form. As regards mammals and birds, at all events, 66 an axiom modern naturalists by no means accept it as in zoological classification that morphological characters alone are to be taken into consideration." VARIATION of another type forms the subject of a paper by Mr. O. C. Bradley in the above-mentioned issue of the Proceedings of the Edinburgh Physical Society. The trapezium of the carpus of the horse is the structure discussed in this communication, and it is shown that this or both limbs, in about bone is present, either in one 50 per cent. of the skeletons examined, while if each carpus be taken separately (that is, without reference to the condition in its fellow) the percentage is a little more than 40. This, in conjunction with its minute size, leads to the conclusion that in the evolution of the monodactyle foot of the horse the bone in question is following in the steps of the lateral metacarpal with which it was originally connected. "The THE article on Dr. True's recent memoir on Whalebone Whales of the Western North Atlantic " which appeared in NATURE of November 14, 1904 (p. 84), has led Mr. F. A. Lucas, of the Brooklyn Institute Museum, to send us some results of measurements of whales made by him at Balena, Newfoundland. Mr. Lucas was one of the party sent to Newfoundland by the U.S. National Museum in 1903 to secure the skeleton and mould of a large sulphur-bottom whale in order that the skeleton and a reproduction of the whale might be prepared for the St. Louis Exposition. If whales grow slowly and require many years to reach their full size, there should naturally be examples of all sizes from small to large among those measured. As a matter of fact, Mr. Lucas remarks that, with the single exception of a female 64ft. long, all the were fairly sulphur-bottom whales examined by him large, and while some were immature and some old, the difference between the largest and smallest was, for such large animals, inconsiderable. With the exception noted the females, ten in number, varied from 68ft. 1oin. to 75ft., the greatest jump being from 71ft. 8in. to 74ft. 4in. Fourteen males varied from 67ft. 7in. to 74ft. 8in., the greatest break being at the commencement of the series, from 67ft. 7in. to 68ft. 11in. No very small sulphurbottom whale was taken during Mr. Lucas's stay, but several young humpbacks were brought in from 24ft. to 26ft. in length. These were still nursing, and it seems fair to assume that a sulphur-bottom whale of the same age (a yearling?) would be from 30ft. to 35ft. long. This seems to indicate that young sulphur-bottoms keep away from the coast of Newfoundland, while the fact that the 64ft. specimen was much younger than those 67ft. to 69ft. long would indicate that up to this point at least whales this were taken grow with great rapidity. As to the size of adult whales, not CONTINUING their notes on the Codiacea in the Journal of Botany (January), Mr. and Mrs. Gepp describe with figures a new species and a new variety of the incrusted alga Penicillus, also a new form of Rhipocephalus Phoenix, which were collected by Mr. M. A. Howe off the Bahamas. Mr. G. C. Druce publishes in the same journal a long list of flowering plants and ferns for which new localities in Berkshire have been recorded since the "Flora of Berkshire " was issued, and Mr. C. E. Salmon discusses Limonium vulgare and its varieties. A LIST of the species of Compositæ from the Island of Formosa which are represented in the herbarium of The Tokio University forms the concluding part of vol. xviii. of the Journal of the College of Science, Tokio. author, Mr. B. Hayate, prefaces his list with an analysis of the genera, thirty-nine in number. Among these seven species, including, of course, Blumea furnishes Blumea balsamifera, the source of Ngai-camphor. Two new species, a Gynura and a Eupatorium, are described and figured. THE limit of an Antarctic phytogeographical zone is discussed by Mr. C. Skottsberg, the botanist of the Swedish Antarctic Expedition, 1901-3, in an article in the Geographical Journal (December, 1904). It has been usual to include in the Antarctic flora the plants of Tierra del Fuego and the Falkland Islands, but Mr. Skottsberg prefers to confine the term Antarctic to a cold desert zone which comprises Graham Land and the islands lying north of it, also the South Shetlands and the South Orkneys, and to distinguish another, the Austral zone, in which the climate permits of the formation of forest or grassland. The two zones differ also with regard to their the Austral flora contains algæ with algal vegetation; floating fronds such as Macrocystis pyrifera and Durvilles utilis, but these are wanting in the Antarctic zone, where calcareous algæ predominate. AN interesting summary of the rainfall of the British Isles for the year 1904 is given by Dr. H. R. Mill in Symons's Meteorological Magazine for January. Taking the British Isles as a whole, the year may be considered as a moderately dry one; the deficiency in the amount of rainfall does not seem to have exceeded 8 per cent.; the extremes noted were 129.3 inches at Seathwaite, and 10.1 inches at Shoeburyness. The whole of the Atlantic border from Cornwall to Shetland had more than the average most marked in the west of amount; the excess Ireland, being as much as 18 per cent. in places, but the east of Ireland was so dry that the whole island exceeded the average by only 1 per cent. In England and Wales there The driest region was a deficiency of about 12 per cent. was occupied the midlands and extended to the Severn on the south-west, the Humber on the north-east, and Yarmouth on the east. The whole of this area had a deficiency exceeding 20 per cent. For the whole of Scotland there was a deficiency of about 8 per cent. ; this was due mainly to the exceptional dryness of the east coast. Dr. Mill loses no opportunity of enhancing the value of his published rainfall tables, and we are glad to learn that all values quoted in future will be referred to an average of thirty years, 1870-99. PARTS xi. and xii. of vol, ciii. of the Bulletin de la Société d'Encouragement contain a review, by M. L. Gruner, of the metallurgical exhibits at the St. Louis Exhibition, and a general account, by M. H. Le Chatelier, of the uses of special steels in industry. THE report for 1904 of the Board of Trade on its proceedings under the Weights and Measures Act contains particulars of a new denomination of Board of Trade standard of 50 pounds weight which has been made and verified in consequence of representations by the Liverpool Chamber of Commerce and the Mersey Docks and Harbour Board. The use in trade of this denomination of weight was authorised by an Order in Council of October 9, 1903. During the past year a number of "Board of Trade standards, the accuracy of which is required by law to be re-determined once in each five years, have been verified in relation to the imperial and metric standards. ALTHOUGH several investigations have been made during the past six years on the deviation of the kathode rays in an electric field, the true nature of the deviation has not yet been satisfactorily determined. In vol. xxxv. of the Sitzungsberichte of the Physico-medical Society of Erlangen, Mr. F. Schneider describes experiments from which, by excluding disturbing factors, he is able to decide that the deviation is of a purely electrostatic nature, and that the dark kathode space has no influence upon it. Variations in the deviation caused by differences of potential and by other circumstances were carefully measured. The same volume of the Sitzungsberichte also contains a discussion, by Dr. A. Wehnelt, of the production of negative ions by incandescent metallic oxides, and an interesting account, by Dr. Ferdinand Henrich, of Liebig's life as a student at Erlangen and Paris. Is the December (1904) part of the Bulletin de la Société d'Encouragement (vol. ciii.), M. H. Le Chatelier criticises the method recently introduced by Mr. Gayley at the Carnegie Steel Works of using in the blast furnaces a current of air which has been freed from moisture by cooling it below o° C. by means of an ammonia freezing machine. It is contended that Mr. Gayley's paper, recently read before the Iron and Steel Institute, contains statements which make it improbable that the alleged economy of 20 per cent. in the fuel used in this process is due solely to the mere desiccation of the air. The principal advantage of drying the air for the blast probably lies in its giving rise to a cast containing less sulphur than ordinary pig-iron, owing to the diminished formation in the absence of water of hydrogen sulphide capable of attacking the spongy iron. Preliminary experiments have shown the probability of this view. We have received from the firm of Ferdinand Ernecke, of Berlin, a catalogue of their lanterns for optical projection; this catalogue is noteworthy because of the description which it contains of methods for demonstrating by pro jection many optical phenomena, such as interference, diffraction, and the behaviour in polarised light of crystalline sections. Messrs. Ernecke, we notice, have acquired the sole right of manufacturing the various forms of the Wehnelt interrupter. In the course of an investigation on the anomalous dispersion of sodium vapour, Prof. R. W. Wood (Proc. Amer. Acad., 1904, xl., 365) has observed that the vapour of sodium possesses a most remarkable viscosity which makes it possible to obtain at one part of an exhausted glass tube a mass of the heated vapour of great density separated by a high vacuum from the glass plates which close the ends of the tube. The tendency of the metal to distil into the colder parts of the tube is extraordinarily small; even after an hour hardly a trace of sodium vapour can be detected beyond the heated portion. The vapour appears to possess a cohesion similar to that of a liquid, and even in a vacuum tube it seems to have a free surface. Potassium, on the other hand, distils instantaneously into the colder parts of the tube. The dispersion of sodium vapour in the vicinity of the D,-line of helium is almost incredibly great; if a prism could be constructed of sodium vapour giving the same deviation as a glass prism of 60°, two lines in the spectrum, separated by a distance equal to one twenty-third of that between the D-lines, would appear separated by a distance greater than that between the red and bluish-green of the spectrum formed by the glass prism. But even this dispersion is small compared with that which obtains within, say, one Ångstrom unit of one of the D-lines of sodium. The variation of the index of refraction with wave-length is shown to conform throughout the range A 2260-7500, except very close to the D-lines, with the simplest form of the dispersion formula developed from electromagnetic considerations for a medium with a single absorption band. MM. H. MOISSAN AND CHAVANNE have taken advantage of the production of metallic calcium on a commercial scale to re-determine some of its physical properties. The specimens which they had under examination contained from 99.3 to 99.6 per cent. of the metal, and were only acted upon slowly by water. Calcium can be easily turned into cylinders possessing a brilliant lustre, tarnishing, however, as might be expected, in moist air. It is sufficiently tenacious to be drawn into wire as fine as 0.5mm. diameter, and these wires were utilised for the determination of the specific electrical conductivity, this proving to be about 16 per cent. of that of silver. The melting point was found to be 810° C. and the density 1.548. The metal was also utilised to prepare calcium amalgam in quantity; this is stable in dry air at the ordinary temperature, and does not absorb either nitrogen or oxygen. The crystalline amalgam corresponds very nearly to the compound Hg,Ca. It is interesting to note that, whilst in a recent list of Kahlbaum metallic calcium is quoted at 6s. id. for 15 grains, or about 9l. per oz., since its manufacture on an industrial scale it can be obtained at 1s. 6d. per oz. THE January part of L'Enseignement mathématique contains a number of papers which should prove of interest to English mathematicians. Dr. J. S. Mackay, of Edinburgh, contributes an interesting account of the life and works of the late Prof. Tait. Prof. Gino Loria gives an account of the progress made and the methods adopted in Italy in the reform of teaching of elementary mathematics, and in particular geometry. Mathematical teaching for engineers forms the subject of a paper by Prof. Jules Andrade, based on his own experiences in the University of Besançon, and finally, M. Louis Couturat, of Paris, contributes a paper on "The Definitions of Mathematics." A SERIES of articles by Mr. E. Edser on the "Electromagnetic Theory" is appearing month by month in Technics, and should prove useful to students of physics. The article contributed to the January issue deals with the electric circuit. A very simple method is given of determining the force on a conductor carrying an electric current perpendicular to a magnetic field, and this result is used to obtain an expression for the electromotive force produced when a conductor cuts lines of force. The results, of course, are well known, and are used by every electrical engineer, but the reasoning by which they are obtained is not so widely understood. Most of the results are determined directly from the properties of lines of force, and the usefulness of the article is greatly increased by careful scale drawings. MESSRS. R. AND J. BECK, LTD., supply, for one guinea, a glass trough, 4×3×0.8 inches, which can be raised or depressed on a vertical metal upright a distance of from 1 inches to 10 inches from the table. This trough forms a simple form of light filter when filled with liquid, and will serve not only as a useful adjunct to a microscope, but for many other purposes where it is of advantage to use a screen for monochromatic light. MESSRS. TAYLOR, TAYLOR AND HOBSON, LTD., have recently issued two series of rapid Cooke lenses that should prove of great service, not only in high-speed photography, but for the finest portraiture and for difficult subjects under fair conditions of lighting. They are known as the Series iv. and ii., and have full apertures of f/5.6 and f/4.5 respectively. The makers have fully developed in these new lenses the advantages of construction of their well-known Series iii. and v. Cooke lenses. The leaflet, which contains details and prices of these lenses, includes some striking illustrations of the work accomplished by them. WE have received from Messrs. Burroughs Wellcome and Co. their photographic exposure record and diary, which is a most handy pocket book and contains many new features. The monthly light tables are now placed at the end of the book, and the order of the months has been reversed so that the current month faces the exposure calculator, each month being torn off as it passes. This renders the calculation of an exposure a very simple process indeed. There is also ample room for recording details of plates exposed, facts relating to positive exposures, and ordinary notes and memoranda, for each of which three separate sets of pages are available. In addition to these and other items of useful information for photographers, there is a serviceable article on exposure, giving complete instructions for using the calculator provided, a concise explanation of the factors governing correct exposure, and an up to date list of the speeds of all plates and films, including, besides British, a number of American and Continental brands. Bound in a neat cover, with pocket and pencil attached, this excellent, cheap, and compact little pocket encyclopædia of photography should be in great demand by all workers, whether amateur or professional. MR. W. B. CLIVE has published new and enlarged editions of parts i. and ii. of Dr. G. H. Bailey's "Tutorial Chemistry." Both volumes have been edited by Dr. William Briggs. THE Engineering Standards Committee has now issued its report on pipe flanges. It is entitled "British Standard Tables of Pipe Flanges," and is published by Messrs. Crosby Lockwood and Son at 2s. 6d. net. THE Department of Revenue and Agriculture of the Government of India has published the agricultural statistics of India for the years 1898-9 to 1902-3, in two volumes. The first part is concerned with British India and the second with the native States. The voluminous particulars have been compiled under the supervision of the director-general of statistics. SEVERAL catalogues of physical, chemical, and other scientific apparatus have been received from Messrs. Brady and Martin, Ltd., of Newcastle-upon-Tyne. Among interesting instruments described in a supplement that brings a larger catalogue up to date may be mentioned Sodeau's new form of gas analysis apparatus, and Seger's cones for the determination of the temperature of furnaces, kilns, &c. A special supplementary list of new apparatus for experiments in physics includes particulars of simple appliances described in recent text-books of practical physics which are largely used in the laboratories of schools and colleges. THE story of the Zeiss works at Jena is of deep interest, both in its scientific and sociological aspects. Prof. F. Auerbach described the Jena enterprise in a volume published in 1903. This work has now been translated into English by Mr. S. F. Paul and Mr. F. J. Cheshire, and published by Messrs. Marshall, Brookes and Chalkley, Ltd., under the title The Zeiss Works and the Carl-Zeiss Stiftung in Jena." A short account of the creation and progress of these great cooperative works was given in the obituary notice of Prof. Ernst Abbe which appeared in last week's NATURE (p. 301). Many other interesting particulars will be found in the English edition of Prof. Auerbach's book, which is a popular description of the development and importance of a concern that offers valuable lessons to students of physics, technology, and social science. JUPITER'S SIXTH SATELLITE.-A further telegram respecting the recently discovered sixth satellite of Jupiter has been received from the Kiel Centralstelle. It contains a statement from Prof. Perrine that the object discovered by him is not identical with Prof. Wolf's minor planet 1905 P.V. The position of the satellite on January 17 at 8h. 44.3m. (Lick M.T.) was R.A. = 1h. 21m. 8s., dec. 7° 17'. A later telegram than the above, published in a supplement to No. 3990 of the Astronomische Nachrichten, states that Prof. Perrine observed the satellite on January 17-702 (G.M.T.), and found that its position with reference to Jupiter was 266° and its distance 36'. EPHEMERIS FOR COMET 1904 e.-The following is the latter part of a daily ephemeris for comet 1904 e (Borrelly) published by Herr M. Ebell in No. 3989 of the Astronomische Nachrichten. 7 +17 7 5 2 17 8 +17 43... O'2133 ... 01638 ... 0:54 Brightness at time of discovery = 1.0 (= mag. 10.0). From the above it will be seen that the comet is now travelling in a north-easterly direction through the constellation Aries, and is observable-although very faintbetween sunset and midnight. SOLAR ECLIPSE PROBLEMS.-In an address read at the International Congress of Arts and Sciences, held at St. Louis in September, Prof. Perrine enumerated and discussed a number of the outstanding problems which still confront solar eclipse observers. The first problem mentioned was that relating to the existence of an intra-mercurial planet, and Prof. Perrine states that this year's eclipse ought to settle the problem so far as the existence of a body brighter than the tenth magnitude is concerned. Such a body would not be above 12 or 15 miles in diameter, and it would take about a million such to account for the anomalies in the motion of Mercury. The movements and velocities of coronal matter are most important problems which should be settled, and, as stations situated so far apart as Labrador and Egypt may be utilised during the coming eclipse, this should offer an exceptional opportunity of solving the problem, because of the length of time between the passing of the shadow at these places. Prof. Perrine suggests the employment of cameras having focal lengths of 40 or 50 feet and pointed directly at the sun, or, where the atmospheric conditions are favourable, longer cameras, mounted horizontally, might be used. The rotational velocity of the corona as regards that of the sun's surface is another problem which he discusses. Finally, he points out the urgent need for a number of well-equipped and well-organised expeditions, and suggests that the interchange of plans and ideas before the eclipse takes place might lead to results of greater value being obtained. THE CONDITIONS IN THE SOLAR ATMOSPHERE DURING 1900-1-An interesting discussion of the conditions obtaining in the solar atmosphere during the minimum epoch of 1900–1, as indicated by the author's eclipse photographs taken in Spain and Sumatra, is given in the January number of the Bulletin de la Société de France by M. N. Donitch, of St. Petersburg. He discusses in turn the spectra of the chromosphere, the prominences and the corona, the form of the corona, and the solar repulsion theory of Prof. Bredichin as applied to the latter. In discussing the spectrum of the chromosphere, he refers to Sir Norman Lockyer's eclipse results, and, in directing special attention to the lines at AA 5317.7 and 4233.8 (Donitch), he states that his results as to the non-agreement of these with the monochromatic coronal radiations incontestably confirm the conclusions arrived at from the English observations. The spectra obtained by M. Donitch show that the prominences may be divided into two types, one composed entirely of calcium vapours, the second containing in addition hydrogen and helium. TRIANGULATION OF THE PLEIADES STARS.-An important addition to the data concerning the positions, the intermutual distances, and the movements of the Pleiades stars is contained in parts vi. and vii., vol. i., of the Transactions of the Astronomical Observatory of Yale University. During 1884-6 the director, Dr. Elkin, made a series of heliometer observations for the triangulation of the Pleiades, and published the results in part i. of the same volume of the Transactions. Since then, however, a new source of systematic error affecting such results has been discovered, and Dr. Elkin has, therefore, re-reduced his observations. The final values are given in part vi., and are therein compared with the similar results obtained at Königsberg in 1840 and those obtained during the more recent triangulation carried out at Yale. The results of these comparisons indicate a motion, in regard to the rest of the group, of 9 out of the 58 stars common to the three researches; the apparent displacements determined from the comparison of the Königsberg and Yale results are shown on a chart accompanying the present paper. Part vii. of the publication contains an account of the second triangulation carried out at Yale by Mr. Mason F. Smith during the winters of 1900-1 and 1901-2, and shows the complete reduction of the observations, together with a final table in which the places of 58 Pleiades stars, for 1885.0, are given with the precession and secular variation values for each. A BRIGHT METEOR.-Mr. J. Ryan, writing from the Manor House, Kensal Green, N.W., states that he observed a very brilliant meteor at about 11.58 on the night of January 27. The meteor appeared about three degrees below Orionis as bright as a star of the first magnitude; it travelled slowly in a path nearly parallel to a line joining and B Orionis, increasing in size until it burst into a green ball when below 8 Orionis, and faded. The complete path was traversed in about 8 seconds. THE GENERAL MOTION OF CLOUDS. THE issue of the Quarterly Journal of the Royal Meteorological Society for October, 1904, contains a translation of the report on the international observations of clouds presented by Prof. H. H. Hildebrandsson to the Permanent International Committee during its session at Southport in 1903. It is not too much to say that this report is one of the most important contributions to our knowledge of the physics of the atmosphere which the last twenty-five years have brought forth, and the Royal Meteorological Society has rendered a substantial service by making the report accessible to English readers. Our knowledge, from direct observations, of the average motion of the air over the greater part of the earth's surface has been in a sense complete for a considerable number of years, but of the currents in the upper air we have until recently had little or no direct information, and all schemes of a general circulation of the atmosphere as a whole have had to substitute hypothesis for fact in dealing with this part of the subject. It therefore became of the highest importance to see whether any direct evidence could be obtained on this point. The most obvious method of attacking the problem consisted in observing the direction and speed of drift of dust or particles suspended in the atmosphere. Dust particles are seldom sufficiently numerous in the upper air to be of use in this connection, but clouds occur in all parts of the world, and their observation is comparatively easy. Even this method, however, has its limitations. Observations are clearly impossible on cloudless days, and it also frequently happens that the upper clouds are obscured by lower cloud forms. water To obtain any general results observations from every part of the earth's surface were essential, and to secure these the ponderous machinery of international cooperation had to be called into play. In the year 1878 a request was addressed to the Permanent International Committee to organise a comprehensive system of cloud observations. After some preliminary consultations a scheme, in which cloud forms were divided into two classes, viz. upper and lower clouds, was adopted, and observations on this plan |