coronagraph operated by Mr. F. McClean obtained a fine photograph of the corona with excessively sharp detail and good extension. The De la Rue coronagraph in charge of Lieut. Trench, R.N., was fortunate enough to secure three negatives, all of which will be very serviceable, as the focus was so well adjusted. Unfortunately the long exposures required for the three-colour camera operated by Lady Lockyer could not be secured in consequence of clouds. The 3-inch Newton, mounted equatorially and worked by Staff-Surgeon Clift, obtained two successful exposures. The instrument in my charge secured four negatives that will prove useful, one of which displays the green coronal ring clearer than those which were secured in the 1898 or 1900 eclipses, and several other distinct coronal rings in addition. The spectrum of the lower chromosphere at the beginning or end of totality was not obtained. The objective grating spectroscope worked by Mr. Howard Payn produced one out of two exposures made, and show's the spectrum of the larger prominences and the green coronal ring.

The observers of the shadow bands gained a great

THI

HIS International Meteorological Conference was opened at Innsbruck on September 9, when Dr. Hildebrandsson, the secretary of the International Meteorological Committee, read the report of the operations of that body on the part of M. Mascart (president) and himself, and explained that at the Southport meeting in September, 1903, Dr. Pernter's proposal that a conference of the directors of meteorological services should be held at Innsbruck this year, similar in character to those at Munich in 1891 and Paris in 1896, was favourably regarded and subsequently adopted.

The vacancies which have occurred on the committee from various causes have been filled by the 72 feet prismatic reflector.

Group packing 6-inch prismatic camera.

Dark room.

amount of information as regards their size, rate of motion, and direction. The coronal sketchers obtained very concordant results, and the other parties gleaned much useful information, which will be published later, as the observations have not yet been brought together.

By the evening of Sunday, September 3, the whole of the instruments, tents, dark room, and smaller huts were comfortably on board, and we steamed away to Palermo, leaving our camp as bare as we found it. Two copies of each negative had been made and separately packed to ensure loss against accident.

With the exception of Mr. Butler, who proceeded to Malta in H.M.S. Venus, and of Mr. Payn, who remained at Palma, our party bade farewell to the officers and men of H.M.S. Venus who had worked so hard, and whom Dame Nature had treated so badly. Crossing to Naples, where we left Mr. F. McClean, we took the train the same morning to Rome, and after a short rest and a little sight-seeing journeyed to Innsbruck, travelling through the beautiful Brenner Pass, to attend the meeting of the Solar Commission of the International Meteorological

appointment of Dr. Palazzo and Dr. Shaw in succession to Prof. Tacchini and Dr. Scott. Dr. Hildebrandsson was elected secretary on the retirement of Dr. Scott, who, since the creation of the committee, had performed this function with a zeal and devotion which would be most gratefully remembered. The following changes have also been made M. Chaves, director of the Meteorological Service of the Azores, was appointed in place of Admiral de Brito-Capello, Dr. Hellmann in succession to Prof. von Bezold, and M. Lancaster in succession to M. Snellen.

Sir John Eliot, having ceased to be director of the Indian Meteorological Service, tendered his resignation as a member of the committee, but, with the approval of the India Office, communicated through Dr. Shaw, the committee invited him to retain his seat, as representing in Europe the Meteorological Service of India. Thus the committee has the great advantage of counting among its members residing in Europe a man of experience and possessing a thorough knowledge of the meteorology of the tropics.

According to the report presented by M. Wild and Dr. Scott to the conference at Munich, and adopted

by it, the principal object of these private conferences of the directors of meteorological services was "the discussion of concrete questions, the arrangements of procedure as to methods of observation and calculation, and the organisation of common investigations." Since that period several investigations have been organised by the subcommittees nominated by the international committee.

The Munich conference nominated a committee for cloud observations, under the presidency of Dr. Hildebrandsson, whose duty it was to publish an international cloud atlas, and to organise and direct observations and measurements of clouds in different

countries during a year. The cloud atlas was published in 1896 by MM. Hildebrandsson, Riggenbach, and Teisserenc de Bort. International cloud observations and measurements were made at a great number of stations from May 1, 1896, to the end of 1897, on a plan fixed by the committee at the meeting at Upsala in 1894. The publications, in accordance with instructions laid down by the subcommittee, have appeared, and the principal results have been published by Dr. Hildebrandsson in a report of which the first part was presented to the international committee at the Southport meeting, and the second part is now presented to the conference. The subcommittee has now completed its work.

an

At the Paris meeting, in 1896, other subcommittees of a similar character were nominated, e.g. aeronautical committee, with Dr. Hergesell as president, for the purpose of organising international scientific aeronautical experiments, especially simultaneous balloon ascents at different stations. A committee was formed under the presidency of Sir Arthur Rücker for the purpose of international researches on terrestrial magnetism and atmospheric electricity.

These subcommittees have had several meetings, and have organised some important investigations. A third subcommittee was constituted at Paris in 1896 for the study of solar radiation. There have been no special meetings, but M. Violle has presented to each sitting of the international committee a report of the principal researches undertaken in different countries. At the St. Petersburg meeting, in 1899, the international committee appointed a telegraphic subcommittee, under the presidency of Dr. Pernter, with the view of suggesting possible improvements in telegrams for weather prediction. Lastly, at the request of Sir Norman Lockyer and Dr. Shaw, the committee appointed a subcommittee for the study of questions relating to simultaneous solar and terrestrial changes, under the presidency of Sir Norman Lockyer.

this

The reports of these subcommittees show that their labours have been of the greatest utility for the By development of meteorological science. means it has been possible to organise and carry out successfully investigations which would have been otherwise impracticable. It is very desirable that all persons occupied with the same or analogous problems should meet periodically, in order to fix ideas and coordinate individual efforts, without in any way restricting personal initiative. It may be asserted with satisfaction, added Dr. Hildebrandsson, that the meteorological conferences organised more than thirty years ago have materially contributed to the develop ment of the science, to uniformity of views, and to agreement between the services of different countries. The constitution of the international committee contributes effectively to the maintenance of good relations, and promotes continuity in the labours of the conferences.

Dr. J. Hann was elected honorary president, and

Dr. J. M. Pernter president, of the conference. In the course of an address Dr. Hann said :

As I am not the official president, I shall take advantage of my privilege of passing over in silence most of the questions which form the programme of the present conference, and I shall devote my attention to certain problems of modern meteorology in which I have a special interest, and the solution of which your discussions will assist.

The use of balloons and kites has brought the exploration of the upper regions of the atmosphere to a degree of development of which we had no idea at the time of the first international congresses at Leipzig and Vienna. Even in 1879 the condition of the question had not changed, when at the congress at Rome I was charged with elaborating plans for observations in balloons and on mountains. We had not then the apparatus for raising kites, and had no idea of the important part they were to play in meteorological science. It was reserved for Messrs. Rotch and Clayton, of Blue Hill, to obtain the excellent results with which we are all acquainted.

we

Further, unmanned balloons were not invented, which since, thanks to M. Teisserenc de Bort, have furnished such surprising data relating to the temperature of the upper regions of the atmosphere. The exploration of the air by means of manned balloons was carried on without any regular plan, and the observations obtained, as found out later on, were unsuitable for scientific investigations. It was only more recently, after the older experiments by Welsh had been overlooked and forgotten, that Dr. Assmann produced his aspiration-thermometer, which is capable of giving accurate temperature observations during balloon ascents.

over those made

on

Thus I was only able to recommend observations in captive balloons. I directed attention to the superiority mountain of such observations summits, which were subject to the disturbing influence of the ground, and gave a daily range of temperature quite different from that observed in free air.

But as observations in captive balloons were limited in several respects, I also recommended that observations

should be made on mountains. Mountain observations, although subject to local influences, are of great use; they give us information that observations made in balloons or by means of kites cannot do, viz. the continuous registration of meteorological elements (especially barometric pressure) at a definite altitude, and are indispensable in determining the conditions of the weather in the higher regions of the atmosphere.

I now

This is one of

come to another domain of research, which at the problem of weather periods and their connection and the present time has attained increased importance, viz. dependance on the activity of the sun. the grandest and most beautiful problems of modern meteorology, for the solution of which astronomers, physicists, and meteorologists must give mutual assistance. One of the services which meteorologists can render in furthering this important object is to obtain suitable observations, by means of which the cyclical variations in the atmosphere and their relations to solar activity may be unequivocally determined.

These observations must fulfil two principal conditions; they must be distributed as uniformly as possible over the globe in order to give sufficient data relating to the conditions of the atmosphere at fixed moments, and must be suitable for closely following the variations in time of these conditions during short as well as in very long periods. The meteorological observations at fixed points must give continuous and homogeneous series of mean and extreme values.

always

Unfortunately, the older observations do not satisfy these conditions. It often happened that the principal meteorological observatories, while constantly endeavouring to obtain more exact data, omitted at the same time to take steps for obtaining comparisons between the old and the new series of observations. This remark applies above all to certain barometrical observations. Thermometrical observations subject to local influences, as well as barometrical observations affected by large or unknown instrumental errors, may afford valuable means for determining the variations of meteorological elements, provided that the local influences and the corrections are

Must we say that the dog is part of nature while the wolf and fox are not? or that methods bad for children over ten are allowable below that age? or must we simply explain the difference as due to composite authorship, permissible in a book of suggestions (not instructions), coupled with some confusion of mind on the part of one author between method and subject-matter?

The true idea of the relative positions which heuristic and didactic methods should occupy, which to our mind is well illustrated by the above simple case of the dog and the wolf, is clearly expressed in the chapter on geography:—

In order that the study of geography may be of real educational value it must not be regarded as a process by which certain facts about the earth. . are committed

a division by methods which will by no means coincide with groups of the present subjects. Even the official time-tables may come to recognise this. On the one hand we shall have heuristic teaching, aiming primarily at training the mind in scientific habits of thought, and incidentally imparting knowledge; on the other hand, didactic teaching to impart knowledge which is wanted but cannot be obtained at first-hand its scope being carefully adapted to the stage reached in heuristic training. But, alongside of these two methods, there still remain a number of other subjects, which do not fall under either of these heads, since they consist in training or drilling of some description, e.g. the use of the mother tongue, singing, handiwork, and health-training. This last, we agree with the writers of the Bluebook, it is not advisable to teach to young children on a physiological basis. Hygienic habits must be learnt before the age at which physiological laws can really be understood, since some knowledge of physics and chemistry is essential to their real understanding; and to attempt to teach them without such a basis is only to give false knowledge, which is only too likely to prevent the acquisition of true knowledge in later years. A. M. D.

Nevertheless, it is not suggested that early geographical teaching shall be purely heuristic. On the contrary, the value of stories of strange and distant countries is strongly urged. At first these are scarcely differentiated from fairy-tales, but with each succeeding year they become more exact, until they at length pass into definite geographical teaching for which an observational basis has meanwhile been prepared. Here we see a development of the idea of the relation between didactic and heuristic teaching. It is useless and unnecessary to think, even as a remote ideal, of the exclusion of the former; all that is necessary is to prevent it from being more precise in character than is justified by the stage attained in the latter.

History, in spite of authoritative opinion to the contrary, we must regard as a science, but one in which heuristic teaching is out of the question. Like the one side of geographical teaching, it grows out of fairy-tales, and there need be no scruple in telling young children traditional stories that have not Survived modern critical research. But we are glad to see that visits to local places of historical interest are recommended, and that in one at least of the schemes suggested in the appendix the syllabus for the highest class includes "first notions on the materials of history and the use of evidence." Unfortunately, very few teachers will have had any opportunity of acquiring the necessary knowledge on this subject. A book treating in a simple manner of the materials of history and by no means confined to the documentary portion is much to be desired.

The Uviol lamps consist of tubes of this special glass of 8 to 30 millimetres diameter and 20 to 130 centimetres length. Platinum wires are fused into the extremities, terminating in carbon heads. In the glass tube there is a charge of mercury of 50 to 150 grs., according to the size. The lamps of various sizes, with their resistance and choking coils, can be connected with electric mains of 220 or 110 volts.

To start the arc, the lamp is tilted to a sufficient degree to allow of the mercury in the tube passing from one pole to the other. At the moment of contact between the pole and the mercury, part of the latter is disintegrated simultaneously with the formation of a column of light. The carbon and heads to the poles permit the passage of the current in either direction without fusing the platinum poles. To get the best results from a current of 220 volts the lamp tube must be 130 centimetres long, but two or three suitable shorter lamps may be arranged side by side or one behind or over the other.

The spectrum of the Uviol lamp is exceedingly rich in lines. The lamp is particularly suitable for taking photographs and for copying processes by artificial light. Experiments have also been made in testing by its means if certain colours used in dyeing and printing have sufficient power to resist the fading effects of the sun. It will thus prove of value in rapidly settling the question of the fastness of colours, which will in future require days instead of months.

The Uviol lamp is also a germicide, and it appears likely that it will prove of value in the treatment of certain diseases of the skin. It is an irritant, and easily sets up inflammations, particularly of the eyes, so that the greatest care must be taken by operators

by means of suitable spectacles. With tactful handling it is said that the Uviol lamp can be used for 1000 working hours without loss of efficiency. The cost of a 400- to 800-candle lamp is id. to 2d. per hour. It thus appears to be a very economical method of converting electrical energy into efficient radiating energy of short wave-length.

NOTES.

THE opening of the bridge over the Victoria Falls on September 12, and the visit of the British Association, were celebrated by a banquet, at which Mr. Newton, representing the British South Africa Company, in proposing the health of Prof. Darwin, welcomed the association on the anniversary of the first occupation of Mashonaland by pioneers fifteen years ago, fifty years after Dr. Livingstone first saw the falls. Prof. Darwin proposed the toast of Sir Charles Metcalfe, representing the great enterprise which to-day marks an important step in advance. Reuter's Agency reports that Sir Charles Metcalfe, in the course of his reply, read congratulatory telegrams from Lord Grey and the directors of the British South Africa Company, and a telegram from Mr. Reunert, president of the South African Association of Sciences, conveying his congratulations that more links had been formed in the chain of civilisation. On September 15 the association received a hearty welcome at Salisbury (Rhodesia). The town was decorated, and the trains were met at the station by the local authorities, headed by the Mayor, the Acting Administrator, and the Resident Commissioner. At a subsequent luncheon the Mayor, in welcoming the members of the association to the most northern part of their tour in South Africa, directed attention to the progress made since the occupation of Rhodesia fifteen years ago. When the many diseases which affect the cattle of the country have been conquered, it is hoped that stock-raising will develop very rapidly. In the course of his reply, Prof. Darwin remarked that when the papers and lectures dealing with the special features of South African scientific work are published, it will be seen that serious efforts have been made to grapple with these problems. Sir Thomas Scanlen welcomed the association on behalf of the Chartered Company; and Lord Rosse and Sir William Crookes also spoke. On September 16, at Umtali, a deputation headed by Senhor de Sousa, secretary of the Governor of Mozambique, met the section of the British Association proceeding to Beira. Senhor de Sousa welcomed the members of the association to Portuguese territory in the name of the Governor, the Mozambique Company, and the inhabitants of Beira. On September 17, at Beira, the visitors attended a reception given by the Governor, and were entertained at luncheon. At 4 p.m. on the same day the party left for home on the steamer Durham Castle. We regret to learn that Sir William Wharton, a member of the British Association party which is returning home viâ Cape Town, is lying ill at the observatory there, having contracted a serious chill.

FOR the past two years cholera has steadily been proceeding westward, and during 1904 had manifested itself in Asiatic Turkey, Persia, and Russia. Since then cases have been recognised in Germany and Austria, and already 179 cases, with 65 deaths, have been recorded in Prussia. A considerable responsibility, therefore, rests on Our frontier guards, the port sanitary authorities throughout the kingdom, particularly in view of the number of aliens

who reach our shores from the region of the infected districts. If cholera unhappily should reach us, it is not likely to cause any serious epidemic. The last epidemics of note in this country were in 1828, 1848, and 1859.

It is announced in the Bulletin de la Société d'Encouragement that next month a museum of industrial hygiene will be opened in Paris by the President of the Republic. The creation of the museum was authorised by a decree of December 24, 1904. Accommodation for the museum has been found at the Conservatoire des Arts et Métiers, and the sum of 41,000 francs considered necessary for the installation has been collected, as well as subscriptions to cover the annual cost of upkeep. The exhibition will be a permanent one, and, being a loan collection, will be constantly renewed.

THE sixth congress of criminal anthropology will meet at Turin on April 28, 1906, under the presidency of Prof. Lombroso. An exhibition of criminal anthropology will be held in connection with the congress.

DR. OSCAR MAY died at Frankfort-on-the-Main on August 25 at the age of fifty. Dr. May (says the Electrician) was one of the founders of the Elektrotechnische Lehr- und Untersuchungs-Anstalt of Frankfort, and was until 1895 instructor in electric lighting at that institution. At the Frankfort Exhibition in 1891 he was a member of the presiding committee and one of the secretaries of the scientific commission.

WE learn from the Victorian Naturalist that the estimates recently presented to the council of the University of Melbourne contain, among other proposals of a scientific nature, provision for the erection of a botanical laboratory and the appointment of a professor of botany, who, it is proposed, shall also act as Government botanist. This arrangement, remarks our contemporary, should ensure the best use being made of the valuable collection of Australian plants in the National Herbarium.

A LETTER from Prof. David Todd, dated September 8, informs us that the print of the solar corona of August 30 which was reproduced in last week's NATURE (p. 484) was from an early developed negative done during the heat of the Sahara gibleh, and was inferior to others developed after the weather turned cool again. He sends us one of these original negatives, which shows a large amount of detail that did not appear in the print reproduced in NATURE. The automatic machine with which these exposures were made took about seventy-five negatives during totality, of which sixty-three proved to be useful for executing drawings of the corona.

DURING the past few days earthquake shocks have been felt in various parts of Italy. The following is a summary of Reuter messages published in the daily papers September 13, Innsbruck.—Severe shock felt in the Arlberg district at 1.30 a.m. Duration, from six to ten seconds. and direction from south to north. September 14Shock felt at 10.10 a.m. at Racidena, Messina, Reggio di Calabria, and Mineo; recorded on the seismic instruments at all the observatories in Italy. Another shock felt at Reggio (Calabria) at 12.33. September 15Mount Vesuvius is becoming increasingly active. During the day frequent undulatory shocks were felt in the region around the volcano. The activity of Stromboli is also very remarkable. September 16, Innsbruck.-Severe shocks felt in the Arlberg district at 4-3 a.m and 4.37 a.m. First shock lasted five seconds and the other four. The shocks were accompanied by loud rumblings. September 17, Monteleone.-Shock felt at 1.40 p.m.