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interest, as it is the only purely insular and tropical station at which anemographic data are recorded in India. The position of the station is well described, and the records are said to represent correctly the winds of the surrounding portion of the Bay of Bengal. At Port Blair winds from north-easterly directions predominate from November to March, or for five months of the year, and winds from southwesterly directions predominate during the five months from May to September. In the transition months of April and October, between the monsoons, winds are very variable. The discussion of the anemograph observations recorded at Dhubri is for seven years to May, 1896. The situation of the station is given in detail, and the anemograph was mounted on a tower, 45 ft. above the ground; its exposure is said to have been excellent. The height of the instrument above the tower is not given. The predominant winds at Dhubri are said to be those up and down the Assam Valley. During November, December, and May down valley winds very largely prevail, but up valley winds are more numerous than down valley winds in February, March, July, and August. Seasonal and diurnal movements of the air are given in tabular form for both stations.
A COPY of the annual report of the Board of Regents of the Smithsonian Institution, "showing the operations, expenditures, and condition of the Institution" for the year ending June 30, 1913, has been received from Washington. The volume runs to 804 pages, of which 140 are concerned with reports and proceedings. The bulk of the book consists of the general appendix which furnishes a miscellaneous selection of scientific papers, some of them original, embracing a considerable range of scientific investigation and discussion. Many of the papers are translations of contributions by distinguished foreign men of science. Among these translations may be mentioned: The reaction of the planets upon the sun, by M. P. Puiseux, astronomer at the Paris Observatory; modern ideas on the end of the world, by Prof. G. Jaumann, professor of physics at the Technical High School at Brünn; recent developments in electromagnetism, by Prof. Eugene Bloch, of the Lycée Saint Louis; oil films on water and on mercury, by Prof. H. Devaux, of Bordeaux; ripple marks, by M. Ch. Epry; the development of orchid cultivation and its bearing upon evolutionary theories, by M. J. Costantin; the problems of heredity, by Dr. E. Apert, principal at Andral Hospital, Paris; the whale fisheries of the world, by M. Charles Rabot; the earliest forms of human habitation and their relation to the general development of civilisation, by Prof. M. Hoernes; feudalism in Persia: its origin, development, and present condition, by M. J. de Morgan, of Paris; shintoism and its significance, by Mr. K. Kanokogi, of Tokyo, in Zeitschrift für Religionspsychologie; the economic and social rôle of fashion, by M. Pierre Clerget, of Lyons; and the work of J. H. Van't Hoff, by Prof. G. Bruni, of the University of Padua. has been the case in former years, many of the articles in the appendix are illustrated by numerous beautifully executed plates.
MESSRS. JOHN WHELDON AND Co., 38 Great Queen Street, Kingsway, London, W.C., have issued a catalogue of books and papers on economic botany which they have for sale. The list, which is conveniently classified, contains particulars of books on commercial plants, tropical agriculture, food plants, and many other branches of economic botany.
THE following forthcoming books of science are announced by Messrs. Constable and Co., Ltd. :"Textbook on Motor-car Engineering," by A. G. Clarke, vol. ii., Design; "Telegraph Engineering," by Dr. E. Hausmann; a new edition of "Wood Pulp," by C. F. Cross, E. J. Bevan, and R. W. Sindall. Mr. John Murray will shortly publish Evolution and the War," by Dr. P. Chalmers Mitchell.
The comet lies towards the southern portion of the constellation of Aquila, in the neighbourhood of the stars 1, 2, and 3 Aquilæ.
The only information to hand regarding the observed return of Winnecke's comet is that mentioned in the Morning Post of April 15. It is stated that Dr. Thiele, of the Bergedorf Observatory, Hamburg, recorded its position on a photograph, the object being of the 16th magnitude. This comet has a period of about 5-8 years, and was first discovered in 1858. At the present return perihelion will not be reached until September, so that later the comet may be a good telescopic object.
Prof. E. C. Pickering, in Harvard Circular, No. 187, gives some early positions of comet 1914e (Campbell). This comet, as the circular states, appears to have been first seen on Thursday, September 17 (astronomical date), at one o'clock in the morning, by Mr. Leon Campbell, at the Arequipa Station of the Harvard Observatory. The comet was then visible to the naked eye. It was discovered independently a few hours later by Dr. Lunt, at the Cape Observatory, and by Mr. Westland, in New Zealand. Six photographs taken by Mr. Campbell were sent to Cambridge, and the positions have been measured and are here recorded.
THE ROTATION OF THE SOLAR CORONA.-M. J. Bosler, in the Comptes rendus for April 6 (vol. clx., No. 14, p. 434), describes the result he has obtained in an investigation on the velocity of rotation of the solar corona. The experiment was made during the solar eclipse of last August, and the apparatus provided the means of photographing the whole spectrum of the corona. It was thought that the green radiation at A 5303 would prove the most satisfactory line for measurement, but its absence rendered this impossible. However, the new red ray (A6374-3) provided the oppor
tunity for the determination, and the result obtained is here described. The photograph secured showed two strips of spectra of the corona at the east and west limbs, and, as comparison spectra, three other strips of spectra of diffused sky light were secured symmetrically on the same plate ten minutes after the eclipse. The resulting wave-lengths of the coronal line for the east and west limbs were found to be as follows, each wave-length being the mean of five complete series of measures entirely distinct :
East 6374-43 (Rowland) West A 6374.59
This difference corresponds to a velocity of 3.7 kilometres, and, making a correction for the inclination of the slit to the solar equator, gives an equatorial velocity of about 3.9 kilometres per second, a value correct to about 25 to 30 per cent. In the eclipse of 1898 Prof. Campbell, using the green radiation, deduced a tangential velocity of 3.1 kilometres a second (±2 km. nearly), the diffuse nature of the radiation preventing further accuracy. M. Bosler points out that the corona moves in the same direction as the surface of the sun, and appears to rotate more quickly. The higher levels of the chromosphere show a similar tendency only to a less degree. An apparent increase in velocity with the elevation is thus proved.
THE ANNUAL OF THE BUREAU DES LONGITUDES, 1915. -The very useful annual for the current year published by the Bureau des Longitudes is as compact as ever, and contains a mine of valuable information very handy for reference. Besides the usual numerous tables useful to the astronomer, several new communications are included. Thus M. G. Bigourdan writes on the subject of the constellations, and after a brief historical sketch gives the co-ordinates of the principal stars and star charts down to 50° S. latitude. Quite a long article, devoted to stellar spectra and their classification, is written by M. A. de Gramont. The author describes Secchi's classification with illustrations of the type spectra, and then refers to more recent classifications, giving a table showing the correspondence with each other. Sir Norman Lockyer's classification is dealt with in a separate section of the article, and is compared with the Harvard College Observatory classification. A very valuable article, covering 162 pages, is that on "Methods of Examination of Mirrors and Objectives," contributed by M. Bigourdan. The article is illustrated by a large number of very useful figures, which will considerably help the reader. The preliminary chapter includes numerous historical references, and this is followed by chapters on general methods of examination, their application to all reflecting surfaces, the examination of mirrors mounted in telescopes, and, finally, a very complete account of the examination and testing of objectives.
CHINESE RECORDS OF ECLIPSES.-In the Proceedings of the Tôkyô Mathematico-Physical Society (January, 1915, vol. viii., No. 1) Messrs. Kiyotugu Hirayama and Sinkiti Ogura discuss the interesting records of early Chinese eclipses. Their working list extends from the earliest solar eclipses to those recorded in the Ch‘un Ch‘iu. In the case of the latter, the calculations are in progress, and are expected to be soon finished. In the present communication the general plan of the calculations consists in determining the central line and the limiting lines for each eclipse. The eclipses of Shu Ching and Shih Ching are dealt with, and diagrams are given showing some of the limits of visibility.
NO. 2373, VOL. 95]
TEACHING OF ENGINEERING IN
THE "Memorandum on the Teaching of Engineer894), recently issued by the Board of Education, is a ing in Evening Technical Schools" (Circular very welcome manual of suggestions to teachers and organisers of schools which provide evening classes in mechanical and electrical engineering.
This Memorandum fills nearly sixty foolscap pages, and is divided into nine sections. An introductory section points out the limitations of part-time courses -courses intended for students whose ordinary employment occupies the greater part of their timewhen compared with full-time day courses. The second section, after referring to the fact that some of the serious disadvantages which characterise parttime courses conducted in the evening may be avoided by the growing practice of holding such courses during the day (the junior employees being allowed "time off" in order to attend them), proposes to classify "a complete curriculum of evening instruction" into three stages: the junior course (fourteen to sixteen); the senior course (sixteen to eighteen or nineteen), and the advanced course (eighteen or nineteen to twenty, twenty-one, or twenty-two). Senior courses are to be of two kinds: a minor course, complete in itself, for apprentices to engineering trades; and a major course, incomplete unless it also includes an advanced course, for technical men. The third section of the Memorandum gives outlines of typical major (senior and advanced) courses in mechanical and electrical engineering, and of minor (senior only) courses in some engineering trades. After making, in the next section, some valuable suggestions upon laboratory and class instruction for adolescent evening students, the Memorandum proceeds, in the following four sections, to consider in more detail the teaching of the various subjects which constitute these outline courses. The accommodation and equipment required for the various classes of work already discussed are considered in the ninth and final section.
The Memorandum is thus concerned with all kinds of evening classes intended for persons employed in engineering work, from the apprentice who is beginning to learn a trade to the designer or manager who attends a course of evening lectures delivered by a university professor. By concentrating attention upon evening classes as such, and especially upon those classes which are primarily intended for boys and young men between sixteen and twenty-two years of age, the Board's inspectors have succeeded in producing a document which cannot fail "to assist teachers and organisers to mark out for themselves the schemes of instruction best suited to the conditions of their classes." But this very concentration, to which the Memorandum owes much of its usefulness, will disappoint education committees or directors of education who look to find in it some treatment of the ing training, such as the following:-The selection, wider educational and economic problems of engineeron democratic lines, of the most suitable boys for each different type of training which should be provided for the different positions in engineering industry; the respective parts to be played, in the preparatory (fulltime) training of engineers, by the elementary school and the junior technical school, the lower secondary school and the senior technical school, and the higher secondary school and the university or technical college; the point at which works training should begin ; the co-ordination of practical experience in the shops with instruction in classes inside the works and with outside schools and colleges; and, more generally, the effective co-operation between engineering firms and
education authorities in establishing and administering schemes for the advancement of apprentices. Perhaps the most important feature of the Memorandum is the distinction which it draws between the major and the minor course. Industrial training has suffered hitherto from a lack of proper appreciation of the differences between the training required by the future artisan (or "tradesman ") on the one hand, and the future "technical" man (whether designer, manager, or commercial representative) on the other. The distinction now drawn does not, however, go deep enough. The Memorandum does not sufficiently discourage the prevailing notion that the ideal evening student first enters evening classes at fourteen, and continues to attend such classes for seven years. Thus, instead of insisting that the technical student should remain at a secondary school until he is at least sixteen, and then, perhaps, enter his major (senior) course when he enters works, the Memorandum contemplates that the technical student and the trade student shall both follow the same junior (evening) course from fourteen to sixteen. It would surely be better that the trade student's own minor course should begin at fourteen instead of at sixteen, and attract him, by its special adaptation to the circumstances of his particular trade, from the moment when he leaves his day school. Moreover, since the trade student will as a rule have less opportunity for general reading in later life, his minor course might well include some "citizenship" subjects, such as industrial history considered at first from the point of view of his particular trade.
More than half of the Memorandum is devoted to "outlines of work" for various recommended courses. This portion is full of most useful suggestions. Some, however, are open to objection, or, at least, to criticism. Thus there is a curious confusion between weight and mass on page 20 ("gx force mass x linear acceleration," which would make g a pure number, independent of the system of units employed). It is also doubtful whether the conception of "work" is really so difficult as to justify the suggested postponement of its introduction until the second year of the senior course. Again, the four years' (major) course in mathematics outlined in the Memorandum might with advantage be less "practical" in its first two years, during which some time might well be found for geometry.
THE HE Mathematical Gazette has recently published a translation of an address delivered by Prof. Gino Loria to the International Congress of Historical Studies. This is a well-proportioned and detached estimate of the main contributions of England to the body of mathematical science, from the earliest available records to the present time. An important suggestion is made that it may be possible to find in some of our libraries manuscript works by some of those early writers who, unlike ourselves, did not hasten to publish their discoveries, and were often surprised by death. In this connection the names of Bradwardine, Richard of Wallingford, John Maudith, and Tonstall are mentioned. Another note is that James Gregory made lengthy stays in Italy, and was therefore probably acquainted with the work of Galileo; so the question arises how far Newton may have been influenced by the achievements of the great Italian philosopher. Prof. Loria suggests inquiry about this as an important piece of research.
Prof. Loria emphasises, with justice, the fact that the renascence of English mathematics in the nineteenth century coincided with a better knowledge and
appreciation of work being done abroad. The greatness of Newton, like that of Euclid and Archimedes, had a sort of benumbing effect upon his successors, and even contemporaries; although, of course, there are exceptions, like Maclaurin and Brook Taylor and Waring. It is also pointed out that even now there are certain branches of mathematics which Englishmen persistently ignore, or else treat by obsolete and clumsy methods. The example given is descriptive geometry; and it is noted that Brook Taylor laid down the principles of this subject in a way perfectly analogous to that adopted long afterwards, and independently, by Fiedler. It is not stated by Prof. Loria, but it is a fact that most of our text-books on descriptive geometry are simply contemptible, from a scientific point of view, and not to be compared with Fiedler's treatise, or the classic work of Monge, which does in the main follow the lines of what we call descriptive geometry, in the restricted sense of orthogonal projection.
Even able students who use these books, and attain great practical efficiency, have no conception at all of the subject as a whole, and are baffled by the simplest problems about traces of lines and planes. So far as we know, there is only one good treatise on descriptive geometry in the English language, and that is in the "Penny Cyclopædia," where so many other treasures have been buried and forgotten. This leads to the remark that Prof. Loria has a proper appreciation of the works of De Morgan, and laments that they are so inaccessible; with this sentiment we cordially agree.
An Italian is as likely as anyone to sympathise with English modes of thought; so any conclusion drawn from this address is likely to be flattering rather than the reverse. We must remember, too, that, when we speak of English mathematicians, we are apt to include such men as Maclaurin, Rowan Hamilton, and Sylvester, who were not Englishmen at all. But even in this inclusive sense of the term "English" one cannot but feel that Continental opinion about English mathematics is almost bound to be analogous to that about English literature in general. Newton is English, and, like Shakespeare, ar Dante, or Goethe, incomparable; but we have lesser men, of a more distinctly national type, who may, perhaps, be more justly appreciated at home than abroad. As an example, we may instance W. H. Fox Talbot, now only vaguely remembered in connection with photography. As a mathematician he is, of course, not to be compared with Abel; nevertheless he did investigate some cases of Abel's theorem in a very instructive and fundamental way, implicitly showing that the theorem is really a deduction from the known facts about symmetric functions of the roots of an equation, and the elementary theory of partial fractions. We are inclined to believe that the simplest proof of Abel's theorem will ultimately follow the lines that Talbot has indicated.
There are many points in the address to which we cannot refer; but one that deserves mention is that Newton is reported to have said that the style of the ancient geometers is the only one appropriate to any mathematical treatise worthy of the name. Judging by the Principia," it is probable that this story is authentic. G. B. M.
PUBLIC HEALTH. THE HE Medical Officer's Supplement to the fortythird Annual Report of the Local Government Board for 1913-14 (Cd. 7612, price 1s. 11d.), while it deals mainly with matters primarily of medical interest, of necessity includes within its scope much that is of value to all scientific minds.
The question of infant mortality occupies a pro.
minent place, and one notes with satisfaction that the general trend of the curve continues in a downward direction. Greater provision is likely to be made in the near future for the care of expectant mothers, and the official recognition of an ante-natal state, though somewhat belated, is none the less welcome. Much good work has been done by voluntary agencies in the past, and the linking up of this with the various organisations dealing with child welfare must inevitably tend to a healthier future race.
Some interesting figures are given regarding vaccination returns. It appears that in England and Wales as a whole one-half of the children whose births were registered in 1912 have been vaccinated, and nearly one-third have been exempted from vaccination by statutory declaration of conscientious objection. When compared with the returns for 1911, these figures show a percentage reduction of 52.3 to 50-1 in the proportion of children born who are vaccinated. The percentage of children born who were exempted under certificate of conscientious objection increased from 28.5 to 32.1.
Inquiries have been made regarding certain outbreaks of enteric fever supposedly due to the conIsumption of infected shell-fish. The medical officer of health of a seaport town has repeatedly referred to the danger incurred by persons in collecting shellfish of all sorts from areas obviously contaminated with sewage. While it is difficult in most cases to prove conclusively that an epidemic owes its origin to such a practice, yet, when local authorities have acted as if such were undoubtedly the case, the wisdom of such action has been abundantly shown by the nonrecurrence of the disease.
Progress is constantly being made towards securing purer and more wholesome food for consumption in this country. A careful watch has to be kept at the various ports of entry to prevent so far as possible the import of unsound and even poisonous material. As an instance of what is continually happening it will suffice to quote the following occurrence. During the unloading of a cargo of sugar in the Port of London it was noticed that some of the bags containing the sugar were covered with borax, which had been carried in the same hold and had become loose
during the voyage. Samples of this powder were taken, and analysis showed them to contain arsenic in considerable quantities. The whole of the sugar was rebagged, and that portion of it that had already been sent out was recalled for suitable treatment under supervision.
The effect of certain types of waters on lead has again been brought into prominence by an outbreak, extensive though mild, of lead poisoning in an urban district in Yorkshire. The waters most liable to act in this way are acid, peaty supplies, and it is even asserted as conceivable that the treatment applied with a view of destroying the plumbo-solvent properties of the water may tend in some way to increase the ability of the water to erode the lead. At all events, further investigation is being made, as the case in point has proved a very difficult one to deal with.
More research has been conducted on the subject of ferro-silicon with special reference to possible danger arising from its transport and storage.
stance, of certain percentage compositions, is liable to disintegration in the presence of moisture, and poisonous gases are given off in quantity sufficient to produce fatal results in human beings. It is suggested that liability to spontaneous disintegration with evolution of poisonous gases may be related to the amount of aluminium present in the ferro-silicon. Further reports are now issued on ferro-chrome and other
ferro-alloys, with special reference to aluminium
The work of Prof. Leonard Hill on the effect of open-air and wind in the metabolism of man is referred to. He points out that the physical qualities of the air-heat, moisture, and movement-are of paramount importance to health. The stimulating effect of cool and variable breezes acting on the skin leads to improved health, while a stagnant, windless, over-warm atmosphere tends to depression and diminished vitality. Two new instruments are described-the kata-thermometer and the caleometer-which enable the rate of cooling of the body and the variability of the rate to be measured (see p. 205 of this issue of NATURE). Prof. Hill's researches on the physical condition of the atmosphere have done much to elucidate the problem of stuffiness," to which so many ailments are undoubtedly due.
THE CARNEGIE INSTITUTION OF WASHINGTON AND SCIENTIFIC RESEARCH. HE Carnegie Institution of Washington was founded by Mr. Carnegie in 1902, when he gave to a board of trustees an endowment of 2,000,000l., to which he added 400,000l. in 1907, and a further 2,000,000l. in 1911. The articles of incorporation of the institution declare "that the objects of the corporation shall be to encourage, in the broadest and most liberal manner, investigation, research, and discovery, and the application of knowledge to the improvement of mankind," and already, as the annual reports of the president and the directors of the various departments show, the objects of the institution are being fulfilled admirably.
The trustees have inaugurated and developed three principal agencies to forward the aims of the institution. In the first place, the departments of research attack problems requiring the collaboration of several investigators, special equipment, and continuous effort. A second agency provides means to enable individuals to complete investigations requiring less collaboration and simpler apparatus; while a third division deals with the publication of the results obtained as the result of the work of the first two agencies.
The reports by the president, the directors of the various departments of research, and the executive committee, contained in the 1914 Year Book, recently received, give full particulars of the financial resources of the institution, and of the activities of its different departments, during the year under review. The Year Book provides convincing evidence of the success of the trustees of the institution in their endeavours to encourage and advance scientific research.
The following table shows the amounts of the grants made by the trustees for the current year, and the purposes to which they are being devoted ::
Division of Publications
The next table shows the departments of scientific investigation to which the larger grants were made for the financial year 1913-14, and the amounts of these grants :
The following extracts from the résumé of the investigations of the year included in the report of the president, Dr. R. S. Woodward, will serve to indicate the nature and extent of the scientific work accomplished during the year.
Although the greater part of the work of the Department of Botanical Research is carried on at its principal laboratory at Tucson, Arizona, it is essential to a comprehensive study of desert plant life to explore distant as well as adjacent arid regions. Thus, having published during the past year the results of an elaborate investigation of the region of the Salton Sea, the department is now turning attention to similar desert basins, of which there are several in the Western States that have been studied hitherto in their geological rather than botanical aspects. These researches are entailing also many applications of the allied physical sciences not heretofore invoked to any marked extent in aid of botanical science. Hence there results properly a diversity of work quite beyond the implications of botany in the earlier, but now quite too narrow, sense of the word. The facilities of the Desert Laboratory have been enlarged during the year by the completion and equipment of a specially designed small building for studies in phyto-chemistry, which has been proved to play a highly significant
rôle in desert life.
The observational, statistical, and physical methods applied by the Department of Experimental Evolution are constantly adding to the sum of facts and of inductions essential to advances in biological knowledge. The range of application extends from the lowest organisms, like fungi, up to the highest, as typified in the race to which the investigators themselves belong. Thus, during the past year, observations and experiments have been made on mucors, plants, pigeons, poultry, and seeds, while the director has continued his fruitful statistical studies in the relatively new field of departures from normality in mankind. The variety of agencies employed in this wide range of inquiry now includes a permanent staff of about twenty members and a physical equipment enlarged during the year by the completion of an additional laboratory and a power-house. Early in the year the facilities of the department were increased by the successful transfer, from Chicago to Cold Spring Harbour, of the remarkable collection of pedigree pigeons recently acquired by the institution from the estate of Prof. C. O. Whitman.
An instructive example of the favourable progress, which may be confidently expected in any field of research when entered by an adequately manned and equipped department devoted solely thereto, is afforded by the experience of the Geophysical Laboratory. In less than a decade this establishment has not only accomplished the formidable task of constructing the necessary apparatus and of preparing many of the pure minerals concerned, but has already begun the processes of analysis and synthesis which are leading
to extensive additions to our knowledge of rock and mineral formations found in the earth's crust. Among the problems under investigation, one of immediate economic as well as of great theoretical interest may be cited here by reason especially of the fact that funds for its execution have been supplied by industrial sources; this is the problem of the "secondary enrichment of copper ores," and the success attained in its treatment demonstrates the practicability of advantageous co-operation between the laboratory and industrial organisations without restriction to scientific procedure and publicity. The section of the director's report devoted to this subject should be of special interest to geologists and to mining engineers as well as to copper-mining industries. A more comprehensive idea of the productive activities of the laboratory may be gained from its publications, which embrace forty-nine titles of papers which have appeared in current journals or are in the press, many of them having been published in German as well as in English.
In accordance with plans recommended by the director of the Department of Marine Biology and approved by the trustees in 1912, an expedition to Torres Straits, Australia, was undertaken in the latter part of the preceding year. Early in September, 1913, the director and six collaborators arrived at Thursday Island in the Straits, expecting to use this relatively accessible island as a base of explorations; but it was soon found advantageous to proceed to Maër Island, one of the Murray group, about 120 miles east-northeast, and near to the outer limit of the Great Barrier Reef. Here a temporary laboratory was set up in the local courthouse and jail, generously placed at Dr. Mayer's disposal by the British authorities. The region proved to be one rich in coral reefs and in marine fauna for the work contemplated. Observations and experiments securing gratifying results were carried out during the months of September and October, 1913. In addition to the critical data secured by Dr. Mayer with respect to the corals about Maër Island, for comparison especially with corresponding data from the corals of Florida waters, observations and materials for important contributions to zoology were collected by each of his collaborators. On returning to America from the southern hemisphere, the director was engaged, during April and May, in two minor expeditions with the departmental vessel Anton Dohrn. The first of these was in aid of the researches of Dr. Paul Bartsch, on cerions, and required a cruise along the Florida Keys from Miami to Tortugas and return. The second expedition was in aid especially of Dr. T. W. Vaughan, long associated with the department in studies of corals and related deposits, and required a cruise from Miami, Florida, to the Bahamas and return. It appears that during its first decade forty-nine investigators have made use of the Tortugas Laboratory, twenty-eight of these having returned two or more times, making a total of 108 visits to this relatively inaccessible centre of research. Of the publications emanating from the department, sixty have been published by the institution, while upwards of forty have been published under other auspices.
The activities of the Department of Meridian Astrometry are concentrated on the derivation of stellar positions for the comprehensive catalogue in preparation, on supplementary measurements of stellar coordinates with the meridian circle of the Dudley Observatory, and on investigations of residual stellar motions. The latter have now become the most important element in the definition of stellar positions by reason of the extraordinary recent progress in sidereal astronomy, to which the department has contributed in large degree. Thus, along with the form