Imágenes de páginas

of Scotland-its geological strata-upside down. There were ent by fortune and already great by birth and political achieveonly two ways of meeting an invader or an innovator such as ments, yet contributed powerfully to the advancement of science. this—with steel or with gold. They must confute him with the It was at symposia such as this that the philosophers of ancient pen or reward him with a medal. The Council had chosen the Greece laid down those great truths of science which had found better part of valour, and he was sure the Society did not amongst this Society such ardent apostles and such illustrious question their discretion. With regard to himself, there was one expounders. The guests on whose behalf he responded, and he remark that he must make. In some of the principal researches himself, expressed sincere acknowledgments for the honour they in which he had been engaged he had worked with colleagues. had done them that night. While, therefore, thanking the Society for the honour they had been pleased to confer upon him, he was, perhaps, not wrong in

The company then separated. thinking that Dr. Thorpe and Prof. Reinold, who had received many marks of appreciation from the Royal, the Physical, and the Chemical Societies, were receiving further, though less

NOTES. direct, recognition from the Royal Society to-day. Apart from all minor questions, the distinguishing characteristic of this A MEETING of the honorary council of advice in connecmeeting was the bringing together of men who were working at tion with the Crystal Palace Electrical Exhibition, which is to different branches of science. These gatherings, and those be opened on January 1 next, was held last week at the Manwhich in the summer take place during the meetings of sion House. The Lord Mayor presided. Mr. Gardner, the the British Association, were, he thought, good for all of them. They checked that scientific particularism which in secretary of the Crystal Palace Company, read the report of the the cultivation of a subject of study ignored the culture of directors, in which they referred to the Electrical Exhibition at the student. They reminded them that they were all co- the Palace in 1881, and to the enormous strides which had since operating to one common end--the promotion of natural know- been made in the industry. The Exhibition of 1881 was recog. ledge. The very speech that he was making bore testimony to

nized as the pioneer of electrical engineering in this country, this fact, for were it otherwise the President would not have called upon an Englishman to reply for our absent foreign

and it was confidently believed that the Exhibition of 1892 medallists, or a physicist to return thanks for honours bestowed would be remembered in history “as showing that the infant on experts in geology and chemistry. It was only because he | Electra has grown to years of maturity, and is capable of further himself believed that there was between scientific men a simi- aiding science, commerce, and the world at large.” The space larity of aim and object, and a community of ideas, which under

available had been over-applied for, and every section of the lay all superficial differences, that he ventured to undertake the task of expressing the thanks in which, he was sure, one and all industry would be well represented. Invitations would be of the medallists most heartily joined.

issued to public bodies throughout the United Kingdom to visit

the Exhibition, where the various systems of electric lighting Prof. Dyer proposed “The Visitors," associating with would be on view, and in this direction alone very great saving the toast the name of the Greek Minister. He said :- of expense to the authorities would be effected, and other

The association appeared to him a peculiarly happy one. advantages must, the directors believed, also accrue. On the The other day he came across a striking statement of Sir Henry motion of Mr. W. H. Preece, the following gentlemen were Maine's—"Éxcept the blind forces of Nature, nothing moves appointed to act as a committee of experts in connection with in this world which is not Greek in its origin." The former

the exhibits : Profs. W. Grylls Adams, W. E. Ayrton, W. influence they could in this Society give some account of. But the latter he regarded with a certain scientific scepticism. Yet

Crookes, D. E. Hughes, A. B. W. Kennedy, J. Perry, and he was not disposed to dispute its validity. We still commenced Silvanus Thompson, Major P. Cardew, Sir J. N. Douglass, oor often arduous mathematical studies with Greek geometry, Mr. W. B. Esson, Mr. Gisbert Kapp, and Mr. Preece. and he could not gainsay those who thought that the influence of the counsels of Plato, and of the precepts of Aristotle, was

On Friday last a portrait of Sir William Thomson, by Mr. unexhausted. In art Greece remained unsurpassed and unsur- Herkomer, was presented to the University of Glasgow. A passable. Some might say that if scientific men had their way number of friends subscribed for it, to signalize Sir William's they would extinguish Greek studies. This was far from the election to the office of President of the Royal Society. The truth. In this Society they rejoiced in those exact studies which presentation was made by Mr. Balfour, the Lord Rector of the recreated the literature and life of the past.

University, who spoke eloquently of Sir William Thomson's The Greek Minister, in replying, said :

great career as a man of science and an inventor. A replica of

the portrait was presented to Lady Thomson. He had always been of opinion that those who were intrusted with the duty of representing their respective Governments THE Egyptian Government has asked the Caisse de la Dette in this country, need confine their watchfulness and activity for £50,000 from the general reserve fund on behalf of the neither to political nor to social circles alone. They had before Antiquities Department. The Cairo correspondent of the Times them a wide and unrivalled field in which to study the benefits accruing to a whole community-to the Government itself—from says that before granting so large a sum the Caisse will probably the efforts of private individuals, when guided by public zeal require the appointment of a Commission to study the purposes and devotion to science ; and he thought no more striking ex- for which it is to be used. It is hoped that searching investiample of such benefits could be instanced than the results of gation will be made into the management of the department the labours of this, the most ancient and most illustrious of

of generally. learded Societies. It might be said to have been born with the first dawn of scientific research in England ; it It is expected that Australia will be well represented at the had remained its stronghold in times of political trouble Chicago Exposition. Exhibits connected with education, and change ; it numbered in its long muster roll all those

minerals, forestry, and especially wool are to be sent. About names which had bequeathed an undying fame to British science; it had worked out and solved, for ihe benefit of the fisty wool growers and wool brokers met lately at Sydney, and State, scientific questions which were elsewhere delegated to decided to despatch a very extensive collective exhibit of official departments alone ; its catalogue of scientific papers was wools. a monument of the world-wide grasp of its subjects. That the achievements of this Society should have been continuous and We have to note a change in the form of the publications ever increasing in importance for close upon 250 years was cha- ssued by the Meteorological Department of India. From racteristic of British public zeal and tenacity of purpose. But January í last, the Annual Reports on the Meteorology of India, what was especially instructive was the ardour with which

which have hitherto been issued about fourteen months after the such work was prosecuted, not only by those whose pursuit was science, but by those especially who, like the illustrious states

termination of the year to which they referred, have been reman at the head of Her Majesty's Government, being independ- | placed by a Monthly Weather Review, the first four parts of which have been received. It is hoped that, when the reference to river and air temperature) the following types :arrangements are complete, these reports will be published (a) Glacier rivers. These are always warmer than the air in from six to eight weeks after current date. The materials used winter, and much cooler in summer ; on the average of the are the morning observations taken at 136 stations, and after- year, they are about 1° colder. (6) Glacier rivers modified by noon observa:ions taken at 82 stations; and eventually, lakes, and rivers from lakes in general. These are, except in a monthly summary of rainfall observations will be given spring, warmer than the air, therefore warmer on the annual for about 2500 stations. The text contains full discus- average. (c) Mountain rivers. Like glacier rivers, these are sions of the chief features of the weather, under each of the warmer in winter and cooler in summer than the air, but the principal elements, illustrated by maps showing the mean difference, especially in summer, is not nearly so great ; so that, distribution of the conditions for the month, and the variations on the average of the year, it is approximately o'. (d) Flat from the mean. The report for January also contains a brief | country rivers. Their temperature is, throughout the year, review of the meteorology of the year 1890, in which it is stated higher than that of the air ; and the annual average difference that conditions were very abnormal in Upper India, and very is over 1°. Sometimes a different relation between river and favourable for a severe winter in the hill districts, and for abun- air temperature is found in the upper part of a river and in the dant rain in the plain districts, while the snowfall in the Kash. | lower, and transition-types occur between thuse above indicated. mir Himalayas and Afghanistan during November and December

The Bahama Islands are soon to be connected with the was abnormally heavy. Temperature was steadily below the average in Northern India, but was excessive in the peninsula. general telegraphic system of Great Britain and the world.

A submarine cable about 200 miles long will be laid from a The Abhandlungen of the Royal Prussian Meteorological point about five miles from Nassau, New Providence, to a Institute (Bd. i., No. 4, 1891) contain the first part of a treatise point about the same distance from Jupiter Inlet, on the southon the climate of Berlin, referring to rainfall and thunderstorms.

east coast of Florida. The cable has been designed for the Berlin possesses a long series of observations, commencing with

Government of the colony by Mr. W. H. Preece. It will be the beginning of the eighteenth century, but in this investigation insulated with gutta-percha, and is being manufactured by some of the earlier observations have not been used. The sub-Messrs. W. T. Henley and Co. It will be laid in January or jects treated of are :-(1) The amount of rainfall, the annual mean February next by the steamer Westmeath, belonging to that being given as 23 inches. The extreme values varied from 14:26 | firm. As the Western Union Telegraphic Company's Floridan inches in 1887 to 30 inches in 1882. The wettest months lines do not at present run so far south as Jupiter Inlet, the were June and July, yielding together 24 per cent. of the annual

station at the American terminus of the cable will be in charge amount. (2) Rain frequency. The average number of days on of the officers of the United States Weather Bureau, who will which more than o'o8 inch fell was 152. The months of greatest transmit the messages to the Western Union Company's rainfall frequency were November and December (3) Hail and

system over their private line. Traffic between England and soft hail (Graupel). The former occurred on 2 to 3 days and the

the Bahamas will thus pass through the Atlantic cables. latter on 3 to 4 days in each year, and mostly in the months May, June, and July (4) Snow. A Berlin winter numbers on an At a meeting held at Aylesbury on Saturday it was resolved, average 33 snowy days. The distribution according to months is on the motion of Sir Harry Verney, that it was desirable to very curious : snow does not occur most frequently in the

establish a County Museum for Bucks, and that an executive coldest months; it falls as osten in March as in December. It committee should be appointed to take the necessary measures. jies on the ground 49 days on an average. (5) Intensity of rain

Letters from various eminent men of science were read at the fall

. Daily falls of more than 2 inches are quite exceptional, meeting. Prof. Flower, writing from the British Museum, and of 14 inches are not frequent. The greatest fall was 1.86

pointed out that a good County Museum, well arranged, neat, inches in i} hours. (6) Wet and dry periods. Attention is and attractive, might be the means of conveying instruction and more particularly given to periods of short duration ; wet periods

giving interest and pleasure to thousands, and that money, of five or more days are fewer than dry periods of similar length; time, knowledge, and sympathetic care must be expended upon the former average 7'5 and the latter 13-2 per year. (7)

it. Prof. Alfred Newton, of Magdalene College, Cambridge, Thunderstorms. Berlin enjoys comparative immunity from

said that the proposal to establish a Museum for Buckinghamthunderstorms, as they occur on an average on only 15 days

shire had his best wishes. He advocated the founding of a

Prof. in the year, about half of them being in June and July. This

maintenance fund, which should be vested in trustees. valuable discussion has been carried out by Prof. G. Hellmann.

Green, of the University Museum, Oxford, contended that in

the proposed Museum care should be taken for the proper selecThe common type of cyclone weather is sometimes materially tion of objects, the primary end being to illustrate the district in altered by orographical conditions. This is the case, e.g., at which it existed. Turin, as recently shown by Signor Rizzo (in a paper to the

DR. ERMLING contributes to the current number of Globus Academy there). He cites thirty-three cases in the last twenty.

There five years, which indicate the general course of the weather

an interesting paper on the Nurhagi of Sardinia. when a cyclone passes over Northern or Central Europe. After

are said to be more than 3000 of these prehistoric buildings

in the island. They are almost all in sertile districts, and fall of the barometer, with strong west wind, the sky clears, the temperature rises considerably, and the moisture of the air

are built in groups which are separated from one another diminishes. This is explained by the influence of the Alps.

by wide and generally barren spaces. According to many The strong west wind is forced up the mountain-range, so that

archæologists, the Nurhagi were tombs ; but the late Canon

Spano, in his “Memoria sopra i Nurhagi di Sardegna,” its aqueous vapour is condensed, and falls as rain and snow on the western slopes and summit. After crossing the ridge, it

published in 1854, contended that they were dwellings and descends, and, having parted with its moisture, appears as a

places of refuge, and this view is accepted by Dr. Ermling. warm dry wind (thus forming an unusual feature in cyclones).

In a trench closed with asphalte, under the ruins of a Nurhage

near Teti, various bronze statuettes, swords, spear-heads, and The temperature of the rivers of Central Europe has been axes were discovered lately by shepherds. These treasures are recently investigated by Herr Forster, of the Society of Geo- now in the museum of M. Gouin, a Frenchman, in Cagliari. graphers at Vienna University ; the monthly and annual means Some of the objects have been analyzed, and it has been found being obtained from stations. He distinguishes (with that the chemical composition of the bronze statuettes is not the same as that of the axes. The statuettes consist of copper hill are five distinct terraces, representing six different shore lines, 90°3, tin 7'4, iron 2'1 ; the axes, of copper 87'4, tin 12'o, lead at elevations of 920, 955, 995, 1015, 1070 feet above the sea, O‘5, with traces of iron.

those at 955, 995, and 1070 being most strongly marked, the last In the new number of Petermann's Mitteilungen Prof.

being the most distinct. Vambéry has a valuable paper on the geographical nomenclature MR. D. MORRIS, Assistant Director of the Royal Gardens, of Central Asia. He gives a list of names, his spelling of which Keu, lately sent to the Entomologist's Monthly Magazine may sasely be accepted as authoritative. The list is to be extended for identification specimens of a Coccid, supposed by him on some future occasion.

to be Icerya Purchasi, received from St. Helena. They

were found there on some rose bushes which had been imported At a recent meeting of the Field Naturalists' Club, Victoria, from the Cape of Good Hope. In a note in the new number Mr. C. G. W. Officer read a paper on supposed human footprints of the Entomologist's Monthly Magazine, Mr. J. W. Douglas on. Folian rocks at Warrnambool. In introducing the subject, Mr. says there is not the least doubt that the specimens received are Officer described in detail the formation and nature of the sand

females of Icerya Purchasi ; and he adds that if the brood of dunes, and their connection with the underlying strata, as shown which they are samples be not extirpated at once by burning by the similarity of the stone now being quarried there. From

all the plants on which they exist, so as to destroy all eggs and an analysis of the stone marle by Mr. Avery, of Queen's College,

young larvæ, they will form the beginning of a pest that must it appears that it contains about 94 per cent. of carbonate of

be intensely serious in such a small island. The probability is lime. Last December a slab was discovered in one of the

that they were introduced as eggs or larvæ, and so escaped quarries bearing impressions which suggested that they were observation. made by human beings. This slab was secured by Mr. Archibald, and placed in the Warrnambool Museum. The deter

. The fourth volume of the entomological publication issued mination of the age of the rocks is of importance, and from the

by the Russian Grand-Duke Nicholas, under the title of evidence of subsidence and elevation which have probably taken

“Mémoires sur les Lépidoptères, rédigés par N. M. Romanoff,'' place since the impressions were made, Mr. Officer is of opinion

contains a very valuable work by M. Gr. Grum-Grshimailothat a considerable lapse of time has occurred since the rocks

“Le Pamir et sa Faune lépidoptérologique,” with were laid down, and he suggests that the impressions were made

coloured plates and a map of the Pamir. Besides its special by two individuals sitting close together and somewhat obliquely tions concerning the geological history of the Pamir. The

entomological part, the work contains some interesting deducto each other. Mr. J. Dennant, discussing the paper, pointed author came to the conclusion, confirmed afterwards on geologi, out that it was necessary to be very guarded in accepting any but the strongest evidence on such questions as those relating to the

cal grounds by Prof. Mushketoff, that during the Miocene period

the Pamir plateau and Tibet formed a continent which rose supposed footprints. Amongst limestone rocks it was well known that mimetic forms were common.

isolated above the great Tertiary sea. It was separated at that

In the Æolian rocks of Cape Bridgewater occurred the so-called fossil forest, which

time from the Tian-Shan Mountains, but seems to have been the casual observer could hardly be persuaded to believe was an

connected with the Altai Mountains, probably through the Bei. accidental resemblance, and nothing more.

Shan highlands. The hypothesis seems probable on orographi.

At the same time Mr. Dennant congratulated Mr. Officer on having produced an

cal grounds as well—the Pamir and the Altai Mountains belong. interesting and highly suggestive paper.

ing to the greatiplateau of Asia of which the Great Altai is one

The rocks were well described, and whether his conclusions concerning the im

of the border ridges, while the Tian-Shan belongs to the series pressions were accepted or not, he had succeeded in drawing them by deep valleys, which must have been filled by the waters

of ridges parallel to the border ridges, and is separated from renewed attention to one of the most striking formations in Victoria.

of a Tertiary sea. The same structure may be observed in East

Siberia also.
MR. J. B. TYRRELL, Ottawa, of the Canadian Geological
Survey, has spent the last two summers in examining the shores

Lists of the Macro-Lepidoptera and birds of Winchester and of Lake Winnipeg, Winnipegosis, and Manitoba ; and he has

the vicinity have been compiled by members of the Winchester

College Natural History Society, and have now been published issued a few notes on his observations, in advance of a more detailed report to the Survey. Speaking of striation, Mr. Tyrrell evidently taken great care to be accurate, and their work

together in the form of a pamphlet. The compilers have refers to many distinct and characteristic glacial striæ which

cannot fail to be of service to students of natural history in the show that during the Ice Age a great glacier, or lobe of the

locality. Mr. A. W. S. Fisher, who signs the preface to the Laurentide glacier, moved south-south-eastward across the lacustral plains of Manitoba, along the valley of Red River to the

list of Lepidoptera, points out that it contains 425 species, which height of land, and onward to near Des Moines, Iowa, sending

have all occurred within six miles of Winchester College. Mr. off branches up the valleys of Swan and Red Deer rivers. The

S. A. Davies, in the list of birds, indicates by an asterisk the

cases in which the birds recorded have been bred within a radius total length of this glacier or lobe, from the north end of Lake Winnipeg to its extreme southern limit in Iowa, would be about

of a quarter of a mile of the College. In most cases, Mr.

Davies himself has found the nest within the last three 850 miles. With reference to moraines, Mr. Tyrrell says the highest at present known in Northern Manitoba are those capping

years. the summits of portions of the Duck and Riding Mountains, ACCORDING to Hering's views, the optical stimulation-value, with altitudes of 2500 to 2700 feet above the sea, or 1800 to or "valence," of a coloured radiation, is made up of one white 2000 feet above the surface of Lake Winnipeg. On the shores and one or two colour valences (the greater the former, the less and islands of Lake Winnipeg a distinct moraine has lately been the saturation). And he has sought to measure the white recognized. In a section on shore lines Mr. Tyrrell describes valences; one useful means lying in the fact that to an eye kept Kettle Hill, on the south side of Swan Lake, as one of the long in the dark all coloured rays of a certain low intensity most interesting monuments of ancient shore phenomena in the seem colourless, but of very different brightness. Hering has whole district. Swan Lake has an estimated elevation of 27 lately had an opportunity of taking measurements on a person feet above Lake Winnipegosis, or 855 feet above the sea ; having sight, but totally blind to colours (a very rare case). and the hill, which appears to have been largely composed of This was a music-teacher, twenty years of age. The experiDakota sandstone, rises 275 feet above it. On the face of this ments (described in Pflüger's Archiv) brought out the fact that


the spectrum of the totally colour-blind is considerably fisheries of Plymouth (continued), by William Roach, Associate shortened ; in this case it began about 665 y, and ceased about Member; note on a British Cephalopod—Illex eblana (Ball), 420 u. The greatest intensity was in the green. Further, it by William E. Hoyle; notes and memoranda. appeared that all coloured radiations had the same relations of

PROF. KAUFMANN, of Liége, has issued a useful “Student " brightness to each other for the adapted normal eye as for the Guide" to the School of Mines and Engineering, the eye of the colour-blind person. With any two spectral lights, Montefiore Electro-technical Institute, and the principal en again, an equality of sensation could be produced in this gineering firms in Liége and the environs. He quotes from an person, when a suitable ratio of intensities was established ;

official report by Mr. Vice-Consul Menzies a statement to the and when the two different colours, which seemed equal to the effect that the advantages offered by Liége from an educational colour-blind, were examined with the normal eye (adapted to

point of view do not seem to be duly appreciated in the darkness), it was found that these two colours had equal white United Kingdom. While the youth of almost all the other valences. In general, the brightness-curve of the spectrum of European nations are fairly, and in some instances largely, the colour-blind had the same course as the curve of white represented at the Liége University, the British students rarely valences for the normal eye. These facts are regarded as a number more than five or six at a time, and sometimes not even strong confirmation of the author's views.

that. The Morgue in Paris now has a medico-legal institute at. A “Handy List of Books on Mines and Mining" has been tached to it, with courses of lectures, &c. The need of frigorific compiled and published by Mr. H. E. Haferkorn, of the apparatus has been long felt, and in a recent competition for the Milwaukee Public Library. He describes it as an alphabetical supply of it, the arrangement proposed by MM. Mignon and reference catalogue, arranged under authors and subjects, and Rouart (Carré's system) has been selected by a Committee, and including analytical references to the contents of important will be worked out. According to the Report (Bulletin de la works. Soc. d'Encouragement), Prof. Brouardel imposed three condi- MESSRS. WHITTAKER AND Co. have issued the fourth edition tions : (1) to submit bodies, on arrival, to a temperature of -15° of the “Working and Management of an English Railway,” by to – 20° C. (this on account of bad conductivity and slowness

George Finlay. In June 1890 the author read d paper at the of freezing internally, also the advanced state of decomposition

Royal United Service Institution, on the transport of troops by often met with) ; (2) to take them into a room with temperature rail within the United Kingdom. The substance of this paper varying between -4° and -1°; and (3) to keep ten bodies at a

he has embodied in the chapter on railways as a means of temperature of -4°. Further, vibration was to be avoided, and

defence. To the present edition he has also added, as the air kept still. The method of Carré, it is known, depends appendix, a lecture (with emendations) delivered at the Society on changes in an aqueous solution of ammoniacal gas, the gas

of Arts, on modern improvements of facilities in railway being driven off by heat, liquefied by its press ure, vaporized, and

travelling absorbed by water. Chloride of calcium is used to transmit the cold ; this liquid passing through pipes in the wooden walls of edition of Dr. A. B. Griffiths's "Treatise on Manures.” It is a

Messrs. WHITTAKER AND Co. have in the press a second a freezing cell, into which the body is pushed on a carriage. Ten hours is enough for the largest body : it becomes hard as wood,

little more than two years since the work appeared. Fisty pages

of new matter have been added. The after-process is easier. Bodies can be kept thus more than eight months, though decomposition had begun before freezing. The third edition of " Electricity, treated Experimentally When an autopsy is to be made, the body is put into a case

for the Use of Schools and Students,” by Linnæus Cumming, which is heated with gas burners, and aster wards it may be has been published by Messrs. Longmans, Green, and Co. relegated to the frozen stale to be kept longer. To keep bodies The author has made such additions and alterations as seemed at - 2° in a hall, for exhibition to the public, presented special necessary to bring the book up to date. difficulties. How these were overcome may be learned from the A NEw edition of Prof. A. Humboldt Sexton's " Elementary above-mentioned Report.

Inorganic Chemistry” (Blackie and Son) has been issued. To The new number of the Journal of the Marine Biological meet the alterations in the syllabus of the Science and Art Association of the United Kingdom (new series, vol. ii., No. 2) | Department, the author has recast the part dealing with opens with the Council's report for 1890–91 and the Director's qualitative analysis. report. The weather was extremely unfavourable for continuous

THE American Association for the Advancement of Science and systematic dredging ; nevertheless the boals of the Labora

has just issued the Proceedings of its meeting (the thirty-ninth) tory were constantly employed on every suitable day, and a

held at Indianapolis, Indiana, in August 1890. considerable amount of material was collected. The preservation of specimens has been much more carefully attended to than

Part 38 of Cassell's “New Popular Educator” has been formerly. One man now devotes almost his entire time to this published. Besides the illustrations in the text, it includes a work. The following are the other contents of the present good map of Spain and Portugal. number :—The egg and larva of Callionymus lyra, by J. T. The second series of lectures given by the Sunday Lecture Cunningham (with plate v.); experiments on the production of Society begins on Sunday afternoon, December 6, in St. artificial baits, by Frank Hughes ; the rate of growth of some George's Hall, Langham Place, at 4 p.m., when Mr. Eric S. Sea fishes and their distribution at different ages, by J. T. Bruce will lecture on “Fogs and their Prevention." Lectures Cunningham ; on some Ascidians from the Isle of Wight-a will subsequently be given by Prof. J. F. Blake, Prof. Vivian study in variation and nomenclature, by Walter Garstang (with B. Lewes, Prof. Percy Frankland, F.R.S., Dr. Benjamin W. plates vi. and vii.); on the development of Palinurus vulgaris, Richardson, F.R.S., Mr. Whitworth Wallis, and Mr. Willmott the rock lobster or sea crayfish, by J. T. Cunningham (with Dixon. plates viii. and ix.); the reproduction and growth of the The additions to the Zoological Society's Gardens during the pilchard, by J. T. Cunningham (with plate x.); the distribution past week include a Barbary Mouse (Mus barbarus)from Barbary, of Crystallogobius nilssonii, by J. T. Cunningham ; physical a Chinese Blue Magpie (Cyanopolius cyanus) from China, iwo investigations, preliminary paper, by H. N. Dickson (with plate Brown Thrushes (Turdus leucomelas) from South America, xi.); notes on meteorological observations at Plymouth, by purchased; a Vulpine Phalanger (Phalangista vulpina), born in H. N. Dickson ; notes on the herring, long-line, and pilchard | the Gardens.


Part xl. of the Transactions of the Berlin Academy of Science MOTION OF STARS IN THE LINE OF SIGHT.-In a paper read photographs should be taken in as many different localities as

for 1890, and Part xxvi. sor 1891. It is very desirable that such before the Royal Society in January 1890, Prof. Lockyer possible, because from them we get the surest basis for con. described a new method of observing spectra of stars and

sideration of the situation and movements of the clouds. But nebula which did away with errors due to the collimator of

valuable aid may be given by the co-operation of numerous the spectroscope not being exactly in the optic axis of the telescope owing to the flexure of the telescope tube.

observers in various regions of the earth without the aid of any

It consisted in using a siderostat to reflect the light of the body


The principal points upon which stress is to be laid in this under observation to a vertical object-glass, whence it was

inquiry are : converged on the slit of a fixed spectroscope. By this means

(1) By what method can the so-called luminous clouds be perfect stability can be secured. This method has been utilized by M. Deslandres, of Paris Observatory, for the photographic

most surely distinguished from others, especially from the

ordinary cirrus cloud ? determination of the displacements of lines in stellar spectra due

Clouds or cloud-like formations which after sunset and before to motion in the line of sight (Comptes rendus, November 23). Comparison spark spectra are taken above and below the no earthly or unearthly sources of light being present on the

sunrise stand out brightly from the dark ground of the heavens, spectrum of the star, and the difference of position of the lines horizon, can only produce this effect by means of their own light common to the star and these spectra afterwards measured. The elements used for comparison are iron, calcium, and

or else by light which they receive directly or indirectly from the

sun or moon below the horizon. hydrogen, and the best results have been obtained with the first

Cloud-like formations which shine at night by their own light of the three. The lines in a spectrum of Sirius, taken on

have doubtless been formerly observed above the surface of the March 3, 1891, in this manner, exhibited a displacement which corresponded to a velocity of recession relative to the earth of 19 i lightning clouds, but also some polar light and meteoric

earth. To these formations belong not only thunder and kilometres per second. But as the earth's motion towards Sirius at the time of observation was 20'2 kilometres per second, the

phenomena. approach of the star to the sun was 12 kilometres per second, various species of self-luminous clouds, for finer measurements

But the so-called luminous clouds do not belong to the The results indicate that considerable advantage is to be gained of their light are wanting, besides which the fact that they are by the use of the siderostat in the study of the radial motions only seen within the zone of twilight proves that the sun below of stars.

the horizon is the principal source of their light. THE VARIATION OF LATITUDE.-Some determinations of It is well known that there are clouds within this twilight the latitude of Cambridge, U.S., made in 1884-85 exhibited a zone which resemble high mountain peaks, and which in the progressive variation, from which, however, no inference was first stages of twilight shine in the light of the sun, though the drawn at the time. The stars observed were contained between latter is below the horizon of the observer. It is easy to deter- 5o and +5° of declination, but a subsequent discussion based mine the relation between the position of the sun below the on more northerly stars (+ 5° to + 50°) gave an exactly horizon, and the height of those layers of atmosphere which corresponding variation in latitude. Mr. S. c. Chandler, in the receive the sun's light and reflect it. Astronomical Journal, No. 248, gives the results of a recent But the laws which govern the whole course of twilight are examination of his values, and from the curve connecting the modified when the distribution of the sunlight-reflecting particles residuals finds the minimum latitude to have been on September in the atmosphere is altered to any great extent. If, for instance, 1, 1884, and the maximum latitude on May 1, 1885, with a numerous minute atoms produced by volcanic eruption or by the range of about o":7.

breaking up of meteoric bodies find their way into those heights. PHOTOGRAPHY OF THE ECLIPSED MOON.-During the lunar

above the earth's surface in which usually the gaseous elements eclipse of November 15, M. Courty, of Bordeaux Observatory,

of the atmosphere are present in a very scattered form, it may took four photographs of the moon after it had entered the happen that such a layer, which reflects the sunlight very earth's shadow. The exposure given was about two minutes, strongly, may curiously alter the course of the twilight. and the disk of the moon could be easily traced on the negatives,

So long after sunset as the masses of air beneath such a layer and on some positives presented with a note by M. Rayet to the

receive direct light from the sun and reflect it, the observer will Paris Academy on November 23. M. Janssen remarked that by not distinguish any deviation from the usual course of twilight. photographing the eclipsed moon and the full moon on the same But as soon as the further sinking of the setting sun gradually plate, and determining the times of exposure necessary to obtain deprives the lower layers of air of the direct light, the higher both images of equal density, a good idea of the relation of the layer of dust still receiving light from the sun stands out in light intensity in the two cases may be obtained.

astonishing brightness, the particles of dust having strong reflecting power, thus giving to the close of twilight the curious

effect of the sudden appearance of shining clouds on the broad PROPOSALS FOR A SCHEME OF CO-OPERA- surface of the heavens.

TIVE OBSERVATION OF THE SO-CALLED The phenomena of the luminous clouds corresponded when LUMINOUS CLOUDS.

first perceived to the above description. At present they are

no longer so strong or so extensive, but only form thin whitishSINCE 1885 curious cloud formations have been seen on blue shining veils, similar in form to the so-called cirrus or

summer nights in both the northern and southern hemi- feather clouds, occupying but a comparatively small part of the spheres, in evident connection with those phenomena which floor of the heavens inside the twilight segment, and in our zone followed the great volcanic eruption at Krakatão. The intense mostly near the horizon. Probably, the layers are now so brightness of these formations, considering the position of the thin that very near and exactly above us they can no longer be sun, denoted that they were situated very far above the earth's seen. surface. Probably these clouds consisted of erupted particles From the above considerations it is clear in what way these thrown to a very great height and there illuminated on summer clouds differ from those situated nearer to us, and especially nights by the sun.

from the cirrus clouds floating scarcely more than 13 kilometres These cloud-like formations, commonly called luminous above the earth's surface. All these lower clouds appear in the clouds, are extremely interesting, both on account of the extra later twilight grey and shadowy on a light ground, because the ordinary height at which they have for years been moving above layers of atmosphere above them are the chief source of the the surface of the earth (more than 80 kilometres) and of the remaining twilight. The luminous clouds differ too in shape movements themselves. A very important point about these and structure from the other kinds of clouds. clouds is that they are—so far as we yet know-visible in each We must guard, however, against the error of mistaking hemisphere only in the summer. It is the more important cirrus for luminous clouds, when, in exceptional cases, the that these phenomena should be carefully and widely observed, former look very bright, in consequence of receiving light either since it is believed that they are gradually breaking up, so that directly or indirectly from the moon or other sources. In this probably in a very few years no distinct traces of them may case, the question is decided by the relatively high degree of remain (see also O. Jesse on so-called luminous clouds, in the stability in position and form of the very high and distant journal Himmel und Erde, vol. i. p. 263).

luminous clouds, as ordinary clouds lie lower and nearer, and Photographic results of the researches of O. Jesse are given in | show much more rapid changes of position.

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