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THE report for 1905 of the Botanical Exchange Club of the British Isles, prepared by Mr. J. W. White, has been received. Besides being the official organ for the publication of notes by the collectors or special authorities on the correct determination of the plants, the report provides a record of new or rare species with the localities in which they have been found. The new records include Caltha radicans for Perthshire, Ulex Gallii, var. humilis, for Cornwall, the aliens Hibiscus Trionum and Bromus unolioides collected in Salop, Lotus tenuis from near Cardiff, and Epipactis atrorubens from Banff. The specific determination of the large-flowered Enothera so plentiful on the Lancashire coast having been questioned, Mr. C. Bailey sent specimens to Dr. O. Focke, of Bremen, who considers that it is probably a form of the famous variable Enothera Lamarckiana.

THE Home Office has issued for 1905 statistics of the persons employed, output, and accidents at mines and quarries in the United Kingdom, arranged according to the inspection districts. The total number of persons employed was 887,524, of whom 858,373 worked at the 3252 mines under the Coal Mines Act and 29,151 at the 688 mines under the Metalliferous Mines Act. At the quarries under the Quarries Act there were 94,819 persons employed. The death-rate from accidents was 1.49 per 1000 persons employed for coal miners and 2.49 per 1000 for metal miners.

WE have received the two latest additions to the valuable series of bulletins issued by the Peruvian Corps of Mining Engineers. In Boletin No. 30 Mr. Carlos E. Velarde gives a detailed account of the means adopted to obviate accidents in the mines of the Cerro de Pasco. Boletin No. 31 is a monograph on the mineral resources of the province of Cajamarca, by Mr. F. Malaga Santolalla. The work covers eighty-three pages, and is well illustrated and furnished with maps and sections. The coalfields of the province are of considerable importance, bituminous coal being worked at Yanacancha and anthracite at Punre. Descriptions are also given of mines of silver-lead ores, of copper, antimony, and sulphur. In fact, the province is one of exceptional mineral wealth.

MESSRS. SWAN SONNENSCHEIN AND CO., LTD., have published a second edition of Mr. C. H. Hinton's book on the fourth dimension. The first edition was reviewed in the issue of NATURE for July 21, 1904 (vol. lxx., p. 269), and it is only necessary to say that the new edition differs chiefly by the addition of a new chapter of twenty-three pages on a language of space. The new chapter is also published separately.

OUR ASTRONOMICAL COLUMN. PHOTOGRAPHING THE CORONA WITHOUT A TOTAL ECLIPSE. -A communication from MM. Millochau and Stefanik referring to a recent note in these columns (May 31, p. 112)| on their proposed method of photographing the corona without a total eclipse of the sun points out that the meaning of part of their note in the Comptes rendus was misinterpreted.

The successful experiments at Meudon dealt with the feasibility of photographing the line at A 5303 with a spectrograph; and others, performed since their communication to the academy was published, have clearly affirmed the possibility of observing the green coronal line when the atmosphere is sufficiently pure and suitable screens are employed. It is this study of the spectrum of the corona that they hope to complete on the summit of Mont Blanc.

OBSERVATIONS OF NOVA GEMINORUM.-The results of some interesting observations of Nova Geminorum, which were made by Prof. Barnard between the date of the

Nova's discovery (March, 1903) and February 27, 1906. appear in No. 6, vol. lxvi., of the Monthly Notices (R.A.S.).

At the time of discovery the magnitude of the Nova was 8.0, but it steadily decreased until at the present time the object is but very little brighter than the fifteenth-magaitude star which slightly precedes it.

The observations made in order to discover any possible difference of focus between the Nova and the surrounding stars indicated no such difference at first, but on September 21, 1903, it was found that the focus for the Nova was 0-29 inch further from the object-glass than that of a tenthIn connection with these magnitude preceding white star. observations a curious feature was noted on March 30, 1903. The Nova appeared to have two distinct foci, both of which gave sharp images. The one image was of about at the 8.5 magnitude, of reddish-yellow colour, and ordinary stellar focus, whilst the second was of the tenth magnitude, about 0-39 inch further out, and of a beautiful crimson colour. On April 6 the crimson image was still present, though not so strong or definite, and on April 27 it had entirely disappeared. This image was probably due to the strong Ha line in the spectrum of the Nova. surrounding comparison stars, of which Prof. Barnard gives a chart, indicate a decrease of distance between one of the latter and the Nova. From this it would appear that the Nova is in motion, but that cannot be stated as a fact until further measures have been made. The measures of the position of the Nova gave no indication of a parallax.

Measures of the distances between the Nova and the

PERSONAL EQUATION IN PHOTOMETRIC OBSERVATIONS.-In No. 4089 of the Astronomische Nachrichten Prof. Ceraski directs attention to the fact that in recording the results of observations made with the Zöllner photometer it very often happens that no mention is made of the relative positions of the real and the artificial stars during the observation, and asks that this should always be carefully recorded by the observer.

There is often an effective personal equation introduced into the results, depending upon whether the real star is to the right or to the left of the artificial star when the observation is made, and as this equation varies with the instrument employed and the magnitude of the variable star at the moment of observation, it becomes important that the conditions should be carefully recorded and the resulting corrections applied when the final values are computed.

COMET 1906b (KOPFF).-In No. 4087 of the Astronomische Nachrichten Herr M. Ebell publishes a newly derived set The of elements and an ephemeris for comet 1906b. following are the elements:

T1905 Oct. 18:6620 (Berlin M.T.)
x=158° 42' 11" 4)

=342° 13′ 35′′ 1-1906 0

i =

4° 14' 32" 4

log 90'522130

The ephemeris shows that the comet has just passed from the constellation Leo, wherein it was discovered on March 13, into Virgo, and is situated about one-third of the distance between Leonis and B Virginis, reckoning from the former.

A note in the Observatory (No. 371) points out that the perihelion distance of this comet is greater than any previously recorded, with the exception of that of the comet of 1729. Prof. Wolf has found an image of the comet on a plate secured on January 14, 1905, more than a year before the discovery, an event which is unique in the history of cometary observations. At that time the magnitude of the object was about 0-4 that at the time of discovery, and approximately equal to the present magnitude.

OBSERVATIONS OF VARIABLE STARS.--Twenty-two newly discovered variable stars in Carina are announced in Circular No. 115 of the Harvard College Observatory. The vari ability of these stars was discovered by Miss Leavitt from the examination of six plates taken with the Bruce telescope, the total number of variables discovered from these plates being now thirty-nine. The star H 1232 is found to

be an Algol variable, and a number of the observations made near minima, together with an ephemeris for May, June, and July, are given in the circular.

A plan proposed by Prof. Bailey for the construction of a variable star Durchmusterung, in which the cooperation of amateur and other astronomers is sought, is described in No. 116 of the same publications.

The results of a number of variable-star observations made by Mr. S. D. Townley at the Lick Observatory during the summer of 1902 are published in No. 95 of the Lick Observatory Bulletins. Most of the stars observed were taken from the "Catalogue of Stars recognised as Variable since the Appearance of Chandler's Third Catalogue," which appeared in the Astronomical Journal eval. xxii.) in 1902.

VISIT OF REPRESENTATIVES OF FRENCH

UNIVERSITY EDUCATION.

THE French visitors have come and gone. To describe in detail the events of a crowded programme would be impossible. We can here only give a brief sketch. From the first meeting on Whit Monday, at the informal dinner given at the Empress Rooms of the Royal Palace Hotel, it was obvious that the entente between the French savants and their English hosts was sincere and cordial, and that it was of much older standing than the political agreement. The Vice-Chancellor, Sir Edward Busk, speaking in French, struck the right note at the outset, and Sir Walter Palmer, the chairman of the reception committee, and Mr P. J. Hartog, the academic registrar of the university (who acted with Mr. W. K. Hill as secretary), both former students of the Sorbonne, welcomed, in the French guests, old teachers and fellow-students.

To the toast of "Our Guests," proposed by Sir Walter Palmer, responses were made by M. Bayet (for the Ministry of Public Instruction), M. Boutroux (for the Faculty of Letters of Paris), M. Lippmann (for the Faculty of Sciences of Paris), M. Chavannes (for the Collège de France), M. Thamin and M. Angellier (for the French provincial universities), M. Morel (for the Société des Professeurs de Langues vivantes), and M. Gautier (for the Guide Internationale), several of whom, including MM. Lippmann and Angellier, spoke in excellent English.

On the following morning the official proceedings began with a reception by Lord Fitzmaurice and Mr. Lough, Parliamentary Secretary of the Board of Education, in the large room of the Foreign Office, followed by luncheon for 300 guests in the East Gallery of the University.

The gallery, which is nearly 200 feet long, was decorated with French and English bunting, and with red, blue, and white flowers; and the French robes of crimson silk (Science) and yellow silk (arts), with the ermine-barred pitoga, the scarlet gowns and many-coloured hoods of the Englishmen, and the light summer dresses of the ladies, formed a gorgeous display. It was a surprise to the Frenchmen, who had been somewhat loth to don academic costume, very rarely worn in France, and only on solemn official occasions, to discover its value in a pageant. One of the most distinguished of them prophesied that the English fashion would before long be followed in France.

Official distinction was given to the reception by the presence of M. Cambon, the French Ambassador, who responded to the toast of the President of the French Republic; and the connection of the University with London Was emphasised by the toast " Welcome to London proposed by Mr. Evan Spicer, chairman of the London County Council, and responded to by M. E. Hovelaque, the French Inspector-General, who has of late years transformed the aching of English in French schools, and who spoke with

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and distinction that Englishmen might well envy. After lunch came addresses in the Great Hall to an audience of about 1800 persons. The Vice-Chancellor gave a brief but interesting sketch of the relation between the University of Paris and the older English universities; M. Liard, the Vic-Rector of the University of Paris, gave an account of the great and fruitful reforms in French secondary and university education, on which, as Sir Edward Busk justly said, he has for many years exerted a commanding and beneficent influence "; Sir Arthur Rücker, principal of

66

the University, showed how the ideal of Adam Smith of free and competitive teaching, and the ideal of Dr. Johnson of an endowed and privileged university were united in the University of London with its external and internal sides, and he amused his audience greatly by pointing out that while the test of "residence" at the Inns of Court was eating, and at Oxford and Cambridge was sleeping, that test in London had been divorced a mensâ et thoro; Prof. Sadler, as past-president of the Modern Languages Association, a number of the French guests of which were entertained by the University, gave an interesting and suggestive sketch of French influences on English education. After the addresses tea was served in the new, and still unfinished, chemical and physical laboratories of the Royal College of Science, over which the visitors were conducted by Sir Arthur Rücker, Prof. Tilden, Prof. Callendar, and the staff of the college. In the evening the guests were invited to meet fellow-specialists informally at parties given by Sir Edward Busk (modern languages and literature), Prof. and Mrs. E. A. Gardner (classics, archæology, and philosophy), Sir William and Lady Ramsay (mathematics and physical sciences), Mr. Mackinder (history and geography), and Dr. Waller, Dr. Farmer, Dr. Halliburton, and Dr. Starling (biological sciences).

On Wednesday morning, June 6, and afternoon, the County Council took charge of the visitors; they were driven in thirty-five carriages, headed by two mounted policemen, from the Royal Palace Hotel to Westminster, where they inspected the Abbey and school, then to the excellent Camberwell School of Arts and Crafts and the Oliver Goldsmith School, and so to Belair, the beautiful park of Mr. Evan Spicer, where lunch was served in an open marquee. The guests returned vid Dulwich College and Picture Gallery, and drove through the Dulwich Common Park, now maintained by the County Council, in which there is a magnificent show of rhododendrons and azaleas. In the evening private dinners were given by the Vice-Chancellor and Lady Busk, the Principal and Lady Rücker, Dr. and Mrs. Bradford, Sir William Collins, M.P., Dr. Headlam, principal of King's College, Mrs. J. R. Green, Sir Philip Magnus, M.P., and Lady Magnus, Dr. and Mrs. T. L. Mears, Sir Walter and Lady Palmer, Dr. and Mrs. Pye-Smith, and the principal, professors, and lecturers of University College.

The evening concluded with a brilliant and crowded reception at the French Embassy.

On Thursday morning, June 7, a series of eight addresses was given in the Great Hall of the University of a singularly varied and interesting character, in which it may fairly be said that the English speakers, Prof. Gardner, Dean of the Faculty of Arts, who spoke in Latin, Dr. Waller, Dean of the Faculty of Sciences, and Sir William Ramsay, who spoke in French, did not fall short of the high literary level characteristic of French eloquence. M. Croiset and M. Appell, the Deans of the Faculties of Arts and Sciences of Paris, M. Léger, professor at the Collège de France, M. Benoist, Rector of Montpellier, and M. Morel, vice-president of the Société des Professeurs de Langues vivantes, gave addresses on which it is impossible to comment adequately. It is understood that they will be published later, when we hope to have occasion to describe them.

On the afternoon of Thursday, June 7, the French guests journeyed by special train to Windsor, where they were introduced by Lord Rosebery, Chancellor of the University, and by the Vice-Chancellor, to the King and Queen, and were afterwards entertained at tea in the Castle; and in the evening the proceedings, so far as London was concerned, concluded with a brilliant conversazione at the University. On June 8 half the guests of the University and of the Modern Language Association were entertained at Oxford and half at Cambridge. The majority left London en Saturday and Sunday, June 9 and 10.

In these festivities there has been much brilliancy, much pomp and circumstance. But behind the show there has been real and solid work accomplished or begun. Lessons are learnt better from men than from books, and the lessons to be derived from French education, to which (with the Army) France has devoted the best part of her energies since 1871, have been sadly neglected by England. We have still to learn that solid secondary education is a

necessary preliminary to fruitful university education; that it is possible to combine literary and scientific training; that both in secondary and in higher teaching, if the teachers are to stimulate individuality in their pupils, they must be given time and opportunity to cultivate and develop their own; that examinations may be used to test the power of taking general views, as well as of remembering an infinity of details; and many other things, which France can teach us. But apart from intellectual profit, there is a moral profit in a meeting of this kind. Blessed are the peace-makers; and the discovery of unsuspected and deep human sympathies between workers in the same intellectual fields, between men and women whose business it is to train up the young minds of their own people, makes for the peace of Europe.

ECONOMIC ENTOMOLOGY.1

(1) SINCE 1867 the State entomologists of Illinois have constantly issued very able reports on noxious and beneficial insects. The first were by Walsh and Le Baron; the last twelve have been by Prof. Forbes, the writer of the present work. In 1894 he issued the first part of "A Monograph of Insect Injuries to Corn." This extended to some 170 pages, with fifteen plates, and dealt only with those insects that attack the planted seed and the roots of corn of various kinds. This dealt mainly with wire-worm, white-grubs or chafer larvæ, ants, aphis, their natural enemies and means of prevention. The second part that has just appeared is very much better than that issued nearly twelve years ago. It treats of the insect injuries to those parts of the corn plant above ground, including stalk, leaves, and ear.

A very excellent plan we do not remember having seen before is adopted in the text, namely, that of grouping the insects under the following three headings: (1) the more important pests; (2) the less important pests; and (3) the unimportant species.

In dealing with the first it is pleasing to note that the insects are dealt with in a strictly practical manner. Such reports as these can well be made to serve a double purpose if properly drawn up as this one is, namely, as a reference book for practical men and also for those who are studying the subject from a student's point of view. The coloured plates, of which there are eight, include the army-worm, corn bill-bugs, the chinch bug, the corn-worm, white-grub, the seed-corn maggot, and other well-known corn pests. The plates are good, and show in some cases, not merely the perfect insect, but the whole life-history and the damage produced on the growing plant.

Among the more interesting sections we find a good account of the damage caused by the chinch bug (Blissus leucopterus, Say) and the means of preventing it, of the army-worm (Leucania unipunctata, Haw.), and of the corn-leaf louse (Aphis maidis, Fitch). In regard to the latter some interesting new observations are recorded, although nothing very definite has been arrived at in regard to the life-history of this corn pest. The author (p. 133) refers to "the failure of all attempts to find or produce a bisexual generation or an alternative food plant of Aphis maidis or to learn how and where it passes the winter."

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Some interesting notes are given on several species of Crambus, called popularly in the States "sod web-worms " or root web-worms" (Figs. 1 and 2). Although we have many species of Crambus in Europe, no very material damage has been recorded. In America we learn that not infrequently these web-worms' become so abundant as to cause brown and deadened spots in a lawn or meadow, sometimes, indeed, deadening the turf as thoroughly as white-grubs or cut-worms can do." Corn seems to be very heavily injured and even completely destroyed over considerable areas in early spring. This is

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1 (1) "A Monograph of the Insect Injuries to Indian Corn." Part i. By S. A. Forbes. Twenty-third Report of the State Entomologist on the Noxious and Beneficial Insects of the State of Illinois. Pp. 273+xxxiii; 238 Figures and 8 Coloured Plates. (Chicago, 1905.)

(2) "Departmental Notes on the Insects that affect Forestry." By E. P. Stebbing, F.L.S., F.Z.S., F. E.S. No. 3, with Preface and Index to vol. i. Pp. 335-469+8 plates. (Calcutta: Government Printing Office, 1906.) Price 25.

corn-worm or cotton-worm is
still called Heliothis armiger,
Hübner, instead of Heliothis
obsoleta, Fabricius, which
antedates it.

A key to the discussion of
insect injuries to corn is given
which will prove very useful
to those studying the subject
in America, and even else-
where, for where species
differ genera often agree in
various parts of the world.
A very complete bibliography
and a copious index complete
the work, which is useful to
us in many regions other than
America.

FIG. 1.-The Sod

Web-worm (Crambus) web (a) containing larva, at base of young corn plant; b, c, injuries to leaf and stem.

(2) This work contains a good deal of useful information and a lot of what appear scrappy notes, which will, however, serve a useful purpose later on. The great difficulty of working at such a subject as the one Mr. Stebbing is engaged upon can only be estimated by those who have attempted the like.

The economic entomologist is often too apt to jump at specific and even generic determinations, or is loth to

FIG. 2. The Common Sod Web-worm (Crambus trisectus): a, adult slightly enlarged; b, back and side views of larva (much enlarged)

publish his observations unless the scientific name can be given. Some groups of insects are almost impossible to name specifically, and many others should only be treated by specialists, who have not always time or inclination to deal with the material sent them.

Nevertheless, it is very necessary that we should record the bionomics of arthropods of economic importance, even though we have to leave to some future date the scientific nomenclature, which in many cases is quite as diverse as the sometimes derided popular one! find in this work valuable information recorded without It is thus pleasing to waiting for even the definite generic status of the pest in question.

From p. 379 to p. 385 is detailed in a most able manner the life-history and workings of probably a Stromatium, which attacks the sandal-wood a cerambycid beetle,

tree.

This "borer" is well known to be one of the most assiduous pests in the sandal-wood area of North Coimbatore, and yet Mr. Stebbing tells us that he is as yet unable to obtain any beetles and that he is not even sure of its generic position. So much is recorded, however, that one has only to find and name the beetle and fill in a few details and the account is complete. The sandal-wood borer will remain the same to the Indian forester, who is indebted to Mr. Stebbing for that work of special value, its life-history, whatever technical name it appears under later on. Other forest enemies are recorded in similar manner; sometimes the genus is doubtful, sometimes the species. The most interesting part of this work deals with the bamboo beetle or shot-borer (Dinoderus minutus, Fabricius). This and allied species are bamboos. often very destructive to

It is shown that this species is the chief pest to bamboos in Calcutta and in the hotter, damper parts of the country, apparently taking the place of the pilifrons in Upper India.

In the account of this pest we find recorded some real practical work with regard to protecting bamboos from the ravages of this insect. The conclusions arrived at show that soaking the rods for five days in water, then drying them and soaking them for forty-eight hours in common Rangoon oil, is the best method of treatment. Other interesting wood-borers are also dealt with, including a goat-moth (Duomitus leuconotus, Walker) found in

Calcutta, Sikhim, and Ceylon, which attacks the Cassia trees just as our goat-moth attacks the ash and oak; and there is also a very full account of the Casuarina bark-eating caterpillar (Arbela tetraonis, Moore), a widespread pest in Casuarina plantations, where it often does much damage.

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An unusual, yet useful, diversion we note in this report is that at the end of each subject are mentioned the points in the life-history requiring further investigation." The plates are for the most part rather crude, but serve their purpose. The photogravure of bamboos tunnelled into by the bamboo-borer is, however, an exception. A great foundation is being prepared in such a work as this; it is only a foundation, but, judging from what we have seen of this and others, it is one upon which we need not be afraid to continue building. FRED. V. THEOBALD.

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THE SOUTH-EASTERN UNION OF SCIEN-
TIFIC SOCIETIES.

was

THE eleventh annual congress of the South-Eastern Union of Scientific Societies was held at Eastbourne on June 6-9 at the invitation of the local natural history society. On Wednesday evening, June 6, the retiring president, Prof. Flinders Petrie, opened the proceedings and gave up his chair to Dr. Francis Darwin, who delivered the presidential address. The title of the latter Periodicity," and in it Dr. Darwin pointed out that one of the most striking features of living things is their periodic or rhythmic character. Life itself may be described as a rhythm made up of alternate destruction and reconstruction. Protoplasm-" the physical basis of life" is alternately falling to pieces by a degradation into simpler compounds and rebuilding itself from the food materials supplied.

In the address simpler instances were mentioned, such as are seen in the process of reproduction, for instance in the case of a plant, which produces a seed that gives rise to another plant, and so on. Again, allusion was made to the seasonal appearance and disappearance of the leaves of deciduous trees. Attention was turned to the time

NO. 1911, VOL. 74]

161

limits between the earliest and latest unfolding of the leaves in various trees and to the attempts which have been made by phænologists to explain these periodic phenomena as being strictly regulated by_temperature.

In the end, however, Dr. Darwin was able to show that temperature, for among other things buds in ordinary the plant is really master of the situation, and not the circumstances will not develop at the end of summer, and at this time it is much milder than in the spring, when they guided by internal rather than external conditions, for the begin to unfold and grow into shoots. The plant is, in fact, bud has to go through certain invisible changes during its winter's rest before it is ready for its normal growth, and these invisible changes are part of the plant's automatic rhythmic capacity which enables it to be independent, to a large extent, of external changes. The same arguments were found to apply to the daily movements of plants. Increase of temperature may cause flowers to open in the morning, but it has no effect at night. Again, leaves that show sleep movements by falling at evening ing, vertical, will, even if kept in the dark, return to their from a horizontal position to one which is, roughly speakoriginal station in the morning. At nightfall the sleep movements again occur, though as the plant becomes more and more unhealthy owing to the absence of light they are gradually lessened. Dr. Darwin described a very interesting case of habit in a sleeping plant, namely, the scarlet runner, which he recently demonstrated. other plants, the one in question adapts itself to one-sided Like illumination by placing its leaves obliquely so that they are at right-angles to the line of illumination, and get the full advantage of the light. If a scarlet runner which has assumed this oblique position is allowed to go to sleep at night as usual, and is then placed in a dark cupboard, it will in the morning assume the diurnal position as already mentioned in the case of other sleeping plants. Most remarkably, however, it does not return to its normal day position, that is, with horizontal leaves, but takes up the oblique position already described. This looks like a psychologically since it might almost be described as an reminiscence of its former position, and is interesting instance of a plant taking advantage of its individual experience.

Another experiment showing how a periodic movement had been induced, and pointing to a kind of memory on the part of a plant, was described by Dr. Darwin, who finally touched upon circumnutation, which he looked upon as the raw material out of which movement in response to stimuli has been developed.

During the congress several papers were read which showed, not only that the neighbourhood of Eastbourne is very rich in plants, birds, and insects, but that there are many keen naturalists in the county of Sussex. instance, Mr. J. H. A. Jenner dealt generally with nature For near Eastbourne, a communication by the late Dr. Whitney and Miss Milner treated upon the flora of the Eastbourne district, while Mr. Ruskin Butterfield compared the birds of Sussex with the list for Great Britain, showing that from the county in question there is a greater number of birds recorded than from any other.

museums.

On Thursday evening, June 7, Dr. Jonathan Hutchinson gave a powerful discourse on the educational value of expensive buildings, and showed the great importance of He emphasised the need for large and inmuseums now that it has been recognised that things, and not words, must be studied if the memory is to be of any real use. He dwelt on a graphic method of teaching history adopted in Haslemere Educational Museum, which he founded, and also alluded at length to the moral effect of proper education.

sea

Two papers dealt with geology, namely, that on erosion and coast defence, by Mr. E. A. Martin, and the geology of the Upper Ravensbourne Valley, with notes on the flora, by Mr. W. H. Griffin. The former contribution summed up the present situation, and was particularly suggestive, while the latter showed how much useful work a naturalist can do who devotes his time ungrudgingly to a particular district.

At the reception given by the Mayor of Eastbourne, Mr. Edward J. Bedford gave a most successful lecturette on bird architecture. The photographic lantern-slides which

illustrated it were particularly good, which, seeing that Mr. Bedford began his work in this direction so long ago as 1890, is not, perhaps, to be wondered at.

The last lecture, on Saturday morning, June 9, to which the teachers of the district were invited, was given by Mr. Wilfred Mark Webb, on nature-study. As two years ago Mr. Webb presented a formal paper to the union, he contented himself, after a few brief remarks, with showing by means of lantern-slides what directions the pursuit in question has taken or might take.

A number of interesting specimens were brought together to form the usual congress museum under the direction of Mr. E. W. Swanton, and the photographic surveys of Surrey, Kent, and Sussex contributed a selection of photographs.

The business done included the election of Prof. Silvanus Thompson as president for 1907, and the acceptance of an invitation to visit Woolwich for the twelfth congress in that year. Dr. Abbott, the founder of the union, its first secretary and late treasurer, was added to the list of vice-presidents, of whom besides Dr. Hutchinson, Mr. F. Merrifield, Mr. F. W. Rudler, the Rev. T. R. R. Stebbing, Dr. Treutler, and Mr. W. Whitaker attended the congress.

The perfect weather made the four excursions to Mickleham Priory and elsewhere a complete success, and a pleasing feature of the meeting was the votes of thanks to local secretaries, Mr. J. J. Hollway and Mr. Sparks, and their coadjutors, as well as that to the general secretary, the Rev. R. Ashington Bullen, which was emphasised by the whole company rising in their seats.

creasing velocity, and falling temperature. These currents end under cloudy skies and with rainfall. In some case the end is caused by the meeting with a cross-current The conclusion is that this air has fed the ascend.ng current, and that the rain has been caused by the expansion and consequent cooling. These trajectories are always from almost due south, and show very little

curvature.

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Class Initial-stage trajectories, commencing regions of fairly still air which may be quite near to the centre of the depression. The meteorological conditions and changes which characterise this class are the rever« of those for class i., even to this extent, that they Bow from low pressure to high. There are many cases of this class shown; too many to suggest a mistake.

Class iii.-Looped trajectories generally cross the track of the depression twice, once in front of the storm and once behind, and may be taken as a continuation of classes i. and ii.

Class iv. Spiral trajectories generally represent cold currents blowing from the east or north round the west of the centre of the depression to replace the southerl currents of class i.

Class v. has three subsections :-(a) trajectories from a point in front of the trough; (b) from a point in the rear · and (c) in the line of the trough. The meteorological conditions accompanying (a) and (b) are similar to those for classes i. and ii. Trajectories in the line of the trough are remarkable for the strength of the wind and for the small and irregular changes of pressure. The accompanying weather is generally cloudy, but without rain.

The trajectories over the Atlantic are obtained from observations made between August, 1882, and September, 1883, and, as only daily records are used, the investi

THE SURFACE TRAJECTORIES OF MOVING gation is on a much coarser scale. Moreover, they are

AIR.1

THE Meteorological Office has just published the results

of an investigation into the movements of the air during storms and periods of barometric depression affecting the North Atlantic and western Europe. The authors deal, not so much with the discussion of theories about cyclones as with the results of direct observations on the direction and force of the winds as recorded at as many stations and as often as possible. Apart from ships' logs,

the records from about 200 stations have been utilised.

The attempt has been made to trace the path of any body of air from the point where it descended from the upper regions of the atmosphere along the surface of the earth to the place where it ascended again, and the method used is briefly as follows:-Using hourly observations whenever possible, arrows have been drawn on a map through the position of the recording station showing the direction of the wind, and the length of the arrow is equal to the distance which the recorded velocity suggests as being the journey of the air during the half-hour preceding and the half-hour following the time of observation. By this method the trajectories are made up step by step through station after station as the hourly maps are made up. Anemometer records are consulted to decide where the velocity of the wind has been sufficiently constant to carry the trajectory properly from one hour to the next.

In the discussion of certain circular storms and barometric depressions which have passed over the British Isles, and which have been selected as typical examples, 162 trajectories were examined, and also the changes in the meteorological conditions along them. Naturally many of these trajectories do not represent the full course of the particular current considered, only the beginning, the middle or the end coming within the region under observ

ation.

These trajectories have been divided into five classes. Class i.-Final-stage trajectories terminating generally, but not always, near the centre or the trough of the depression. These are marked by diminishing pressure, in

1 "The Life-history of Surface Air-currents; a Study of the Surface Trajectories of Moving Air." By Dr. W. N. Shaw, F.R.S., and R. G. K. Lempfert. (London: Published by the Authority of the Meteorological Committee, Wyman and Sons, Ltd.) Price 7s. 6d.

more open to criticism, for there may be many changes in the meteorological elements in twenty-four hours. Some of the trajectories traced are remarkable for their length; for example, between December 23 and 30, 1882, one is traced from West Africa to North Russia, and another from Florida to the British Isles, and between November 1; and 17 one is followed from Hudson's Bay to the Adriatic.

In seeking to locate the positions of ascending and descending currents and the connection between these and the distribution of rainfall, it has been taken as proved that an ascending current of air is necessary for the production of measurable rainfall, and we are reminded that it is not necessary or usual for these ascending or descend ing currents to be vertical. They are generally verv oblique. The approximate positions of ascending currents are located by noting the convergence of air to such places, divergence denoting descension.

Convergence may be produced by the trajectories being directed towards one point, or by air overtaking air which is preceding it in the same direction, or by the wind blowing towards a persistent cross-current. These are obvious and typical cases.

If two sets of isochronous points or trajectories be joined by lines, then the ratios of the enclosed areas will indicate convergence or divergence according to whether the second area is smaller or larger than the first.

The greater convergence takes place almost always in front of the centre of the depression, and this agrees with the area of greatest rainfall. As, however, the rain is generally brought by southerly winds, the rainy district is somewhat to the north of the area of convergence, the current evidently having continued its onward whilst rising.

course

Some of the general conclusions deduced during the investigation may be given :

(1) In the front portion of travelling storms there is air moving from high pressure to low and to lower temperature and rainfall, while in the rear, even quite close to the centre, there is movement from low pressure to high and towards improving weather conditions.

(2) Fast-travelling storms receive air from the right hand (south) of the path in front of the storm, and lose an equivalent amount from the rear at the same side Slow-travelling storms receive air from the south direct to

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