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microbes involved in ensilage of green fodder, and of the besides. He hoped that in the efforts that were being made to variations of sugar and acidity with temperature and time. | insure education in everything which was required for the trade (11) The development of Triclades. (12) The development of of the country they would not forget that there were other the spleen. The prize offered in each case is a gold medal or a things besides that, Some of the greatest discoveries made sum of 150 forins. Memoirs may be written in Dutch, French, by Davy, Faraday, and Pasteur, were not made for trade English, Latin, Italian, or German (not German characters), purposes, but in the interests of abstract science. If they did and they are to be sent in, with sealed packet, to the secretary anything to delay the development of science as a whole, they before January 1, 1893. (Further particulars in the Revue would hinder trade in the long run. Abstract science might Scientifique, October 10, 1891.)

sometimes appear at first to be very abstract, but all at once it ACCORDING to an official report which reached the Japanese might turn out to be of the utmost value in connection with Legation, London, on November 6, the earthquake of October trade. He would be very sorry indeed if in the future technical 28 affected the prefectures of Aichi and Gifu. It was calculated instruction should push other education out of the field altogether. that the number of persons killed was 6500, and of persons

There was a danger of this, because the funds available for injured 9000; that 75,000 houses were destroyed, and 12,000

education and objects of that kind were limited, and what was damaged.

devoted to one institution was to some extent taken from others. In its review of the weather during October, the U.S. Pilot

The annual report on the technological examinations of the Chart notes that the latter part of September and nearly the City and Guilds of London Institute has just been published. entire month of October were characterized by exceptionally aminations committee, and Sir Philip Magnus, superintendent

It is signed by Mr. G. Matthey, F.R.S., chairman of the ex. severe weather in the North Atlantic. Tropical hurricanes passed north between Hatteras and Bermuda on October 3, 12,

of technological examinations. The facts set forth in the

At the recent exand 18. The heavy weather that prevailed between Newfound report are, upon the whole, satisfactory. land and the British Channel in the last week of September was amination the total number of worked papers was 7416, as followed by comparatively moderate weather during the first two against 6781 in 1890, showing an increase of 635, the corredays of October, but a storm that apparently moved eastward in sponding increases in the two previous years being 175 and 440. high latitudes on the 2nd and 3rd caused increasing westerly

This year, too, there is not only an increase in the number, but gales in mid-ocean, and the force of these gales was very greatly

also in the proportion of candidates who have succeeded in increased by the formation of a secondary on the 4th, a short satisfying the examiners, the number of passes being 4099 as distance west of Rockall. This secondary remained central

against 3507 in 1890, and the percentage of passes 55'3 as about the same place for three days, the 4th, 5th, and 6th, and

against 51 8. Moreover, the examinations were held this year during all of this time there was very severe weather almost all

in 53 as against 49 su bjects in the previous year, and in 245 as the way from the North Sea to the Grand Banks. There were

against 219 different centres throughout the country. also later storms, and altogether, when the facts are fully Writing to the Times on the place due to horticulture in known, it will probably be found that the month was one of the technical education, Mr. W. Wilks, honorary secretary of the most severe on record.

Royal Horticultural Society, says that that Society is ready to We take from Symons's Monthly Meteorological Magazine for

co-operate with the County Councils in any attempt to promote October the following interesting details of the climate of the

the serious study of the subject. The Society has already British Empire during 1890. The tables for the year exhibit

entered into arrangements with the County Council of Surrey some exceptional features. For the first time in the 17 years that

sor holding examinations and awarding certificates, &c., after a the figures have been published, the highest shade-temperature

series of lectures in various centres ; and the County Council of occurred at an East Indian station, 105°•6 at Calcutta, instead

Cambridgeshire is in communication with the Society as to the of in Australia. The highest sun-temperature was, however, re

provision of practical demonstrations of scientific methods applied corded at Adelaide, 163°9, although it is not exceptional for

to orchards, allotments, and cottage gardens. Mr. Wilks is this to occur at Calcutta, while the mean temperature of the

also in correspondence with a gentleman in Somersetshire, with East Indian stations far exceeds that of Australia. The lowest

the object of sending round an itinerant instructor and adviser shade-temperature occurred, as usual, at Winnipeg, - 39°4, the to some of the cider orchard districts of that county. extreme rigour of whose winters far exceeds the cold at the other At a meeting of the Ashmolean Society in the Museum, OxCanadian stations. The greatest range in the year, 135°-9, as ford, on Monday, November 9, under the presidency of Prof. well as the greatest mean daily range and the lowest mean tem- Odling, Colonel Swinhoe read a paper on silk-producing moths. perature, 32°:8, also occurred there ; while the least yearly range, The author exhibited specimens of Bombyx mori and of Their 25°:4, and the highest mean temperature, 80o5, occurred at cocoons, showing the changes produced by variation of climate Colombo, Ceylon. The driest station was Adelaide, mean and domestication on members belonging to the Bombycidæ. humidity 62, and the dampest London, mean humidity 80. Several specimens of the tussur silkworm were exhibited, illusThe greatest rainfall for the places quoted was 82'90 inches at trating in some respects the effects of cross-breeding, which, in Trinidad, and the least, 19'96 inches at Jamaica. The most the opinion of the author, had done much to depreciate the cloudy station was Hobart, in Tasmania, and the least cloudy commercial value of the silk produce of India. Much greater Malta. A large amount of cloud occurs at most insular stations, care—a care which the Chinese appreciated—was needed on the as well as great humidity, and small range of temperature ; and, part of the native breeders of the silkworm to insure in the silk at one time or another London, Ceylon, Barbados, and Mauritius the peculiar qualities which enhance its market value. A dishave recorded the extremes of most of these elements.

cussion followed, in the course of which Prof. Legge described At the distribution of prizes in the Sheffield Technical School | briefly the method of culture of the mulberry-tree in China, and last week, Dr. Sorby, the President of the Council of Firth

some of the methods employed in winding and securing the silk. College, spoke vigorously and opportunely on a subject which is The Christmas lectures to juveniles, at the Royal Institution, likely to become one of increasing importance—the true relation will this year be on “Life in Motion, or the Animal Machine" of technical education to the study of pure science. He feared, (experimentally illustrated), and will be delivered by Prof. John he said, not that technical education would not succeed, but G. McKendrick, F.R.S., Professor of Physiology in the Unithat the public might forget that there might be something else versity of Glasgow.

[graphic]

A MAMMALIAN tooth has just been discovered by Mr. spheres. One use of ozone, on which Herr Frölich lays special
Charles Dawson, of Uckfield, in a Wealden bone-bed near stress (in the recent lecture from which these data are taken),
Hastings. The fossil much resembles one of the lower molars is the disinfection and sterilization of water. And doubtless
of Plagiaulax, a genus well known from the Purbeck Beds of with an abundant supply of the substance, the use of it would be
Swanage. It is the first evidence of a mammal from the greatly extended.
Wealden formation, and will be exhibited and described by

MR. A. CRAWFORD, the manager of the travelling dairy Mr. Smith Woodward at the next meeting of the Zoological connected with the Department of Agriculture, Victoria, is Society, on the 17th inst.

able to give a very favourable report of the results of the DE CANDOLLE states, in his " Origin of Cultivated Plants," operations of the dairy during the last two years. It has been that maize is unknown in the wild condition. Some light may the means, he says, of very largely improving the general possibly be thrown on the origin of cultivated maize, by the average of both cheese and butter sent to market. A good discovery of a wild species, the only one of the genus, in many pupils have been taught who had never made butter or Mexico. It is described by Prof. Sereno Watson, in the cheese before, and several of them are now managing factories. Contributions to American Botany,” under the name Zea In nearly all the places he has visited Mr. Crawford has lectured nana.

on dairy farming; and in many cases he has gone to outlying

districts as well as to important centres. We learn from the Journal of Botany that the great Index of Genera and Species of Flowering Plants, on which Mr. B.

At the recent general meeting of the German Anthropological Daydon Jackson has been continuously engaged for nearly ten

Society, Prof. Montelius, of Stockholm, delivered two remark. years, is now ready for the printers' hands, and will be issued

ably interesting archæological lectures. In the first he dealt by the Clarendon Press, under the title “Index Kewensis

with the chronology of the Neolithic Age, especially in nominum omnium plantarum phanerogamarum, 1735-1885."

Scandinavia. The monuments of that age, he said, belonged The work has been carefully revised by Sir Joseph Hooker,

to three different periods. First, were free-standing dolmens who, besides annotating the manuscript, has undertaken the

without passages; next, passage-graves ; finally, stone cists, care of the geographical distribution.

The last are later in proportion to the completeness with which

they are covered by the mounds heaped over them. Behind If the weather during the approaching winter be as severe as

the periods represented by these classes of monuments was a That which we had last winter, many persons iwill be likely to Neolithic period from which no grave of any kind is known to take some interest in an invention which is attracting notice in have survived. It has left traces, however, in its implements, America. This is an electric snow-sweeper-a snow-sweeper

which are of an earlier form than the various sorts found in the driven by an electric motor. The Engineering Magazine, of different groups of monuments. The Scandinavian forms of New York, says that while the machine is driven along the track Neolithic weapons, implements, and ornaments are closely akin of an electric railway by a motor of 30 horse-power, taking its

to those which have come down to us in the rest of Europe, current through the trolly wire, the two sweeping brushes are especially in North Germany, England, Italy, and even Cyprus. each driven by an independent motor, and all the three motors This may be held to prove that there was a more or less active are reversible. It is stated that this plough is competent to re

commercial intercourse between Scandinavia and the Continent move from a track snow having a depth of from 3 to 12 inches,

at a very remote time. To this commercial intercourse Prof. while running at a speed of from 4 to 10 miles an hour. The Montelius is disposed to attribute the relatively high civilization independent action (of the brush-motors enables them, when of Scandinavia in the Neolithic Age. Prof. Montelius also necessary, to be run at a high rate of speed while the plough is contends that the various periods of the Neolithic Age in moved slowly along the track, and thus to cut away hard, com.

Scandinavia were more nearly contemporaneous with those of pacted snow, or drifts

. It is said that the machine was thoroughly other parts of Europe than has hitherto been generally supposed. tested last winter, and its effectiveness thereby completely de- In his second lecture Prof. Montelius treated of the Bronze monstrated.

Age in the East and in Southern Europe. He distinguished the It is known that ozone can be abundantly produced by the following periods :-(1) A copper period without bronze, reelectric silent discharge, and many years ago Siemens devised presented by the finds of Richter in Cyprus and those obtained an "ozone-tube” for the purpose, consisting of two thin glass by Schliemann from the first city at Hissarlik. (2) The bronze tubes, one within the other; the inner lined, and the outer period in the islands of the Ægean Sea, Rhodes, Crete, &c. coated, with metal, to which alternating currents of high tension

(3) A later bronze period-(a) with shast tombs at Mycenæ, are brought, acting on the gas to be ozonized within. From

(6) with bee-hive tombs in the neighbourhood of Mycenæ, recent experiments in Siemens and Halske's laboratory, it

Orchomenos, &c. These cities had not a pure Hellenic civiliza.

The

tion, but must be regarded rather as Oriental colonies. appears that a good result may be had with only one dielectric, and for this not only glass, but mica, celluloid, porcelain, or the knowledge of bronze certainly came to Europe from the East ; like, may be used. Thus the ozone-tube may be arranged with

not by way of Siberia and Russia, nor across the Caucasus, but 2. metallic tube within, and the outer tube a metal-coated probably through Asia Minor and the Mediterranean to Italy dielectric ; or the inner metal tube may have a dielectric coat,

and Spain, whence it rapidly spread to Gaul, Britain, and other

countries. while a metal tube is the inclosing body. As metals that are little or not at all attacked by ozone, platinum, tin, tinned A PENINSULA called Keweenaw Point, jutting into Lake metals, and aluminium are recommended. Through the inner Superior from the southern shore towards the north-east, is tube flows cold water, and through the space between the tubes famous as the centre of a vast copper-mining industry. Last air, dried and freed from carbonic acid. Several such tubes year the mines produced no less than 105,586,000 pounds of re may be combined in a system, and worked with alternate fined copper, and it is estimated that during next year production currents (for single tubes the continuous current with commu- will be increased by at least 20 per cent. Mr. E. B. Hinsdale, tator is best). An apparatus of this kind is now at work in the who contributes to the latest Bulletin of the American Geo. laboratory, yielding 24 mg. of ozone per second. Experiments graphical Society an article on the subject, has much that is are being made in supplying compressed ozone for technical use; interesting to say about the numerous prehistoric mines which and this has been accomplished with a pressure of nine atmo- have been found in this region. These ancient mines—judging from their extent-must have been worked for centuries. Who take care of the ornithological collection, offered to send it to the workers were, no one can tell. They seem to have known Mr. L. Stejneger, of the U.S. National Museum, in instalments nothing of the smelting of copper, for there are no traces of for identification and study, and the proposal was gladly acmolten copper. What they sought were pieces that could becepted. Dr. Stejneger has made some progress with the work, fashioned by cold hammering into useful articles and ornaments. and has just issued “Notes " in which he presents the results of They understood the use of fire in softening the rocks to enable his examination of the first instalment. He has had the satisthem to break away the rock from the masses of copper. They faction of finding “quite a number of interesting additions to could not drill, but used the stone hammer freely. More than the Japanese avifauna.” ten cart-loads of stone hammers were found in the neighbourhood of the Minnesota mine. In one place the excavation was about

We have received Nos. 7-9 of vol. i. of “Illustrations of the 50 feet deep, and at the bottom were found timbers forming a

Flora of Japan, to serve as an Atlas of the Nippon-Shokubutscaffolding, and a large sheet of copper was discovere i there. In sushi,” by Tomitaro Makino, a monthly publication, brought another place, in one of the old pits, was found a mass of copper

out in Tokyo, apparently somewhat on the plan of the " Icones weighing 46 tons. At another point the excavation was 26 feet

Plantarum." Each number contains about six plates (undeep. In another opening, at the depth of 18 feet, a mass of coloured), with descriptions, of new or remarkable species, copper weighing over 6 tons was found, raised about 5 feet from natives of Japan. The drawings are exceedingly well done, its native bed by the ancients, and secured on oaken props. and the descriptions (in English) would compare favourably, in Every projecting point had been taken off, so that the exposed accuracy and completeness, with those of some works published surface was smooth. Whoever the workers may have been,

in this country. The species described appear o be taken at many centuries must have passed since their mines were random, those in the same number having no affinity with one abandoned. Their trenches and openings have been filled up,

another. or nearly so. Monstrous trees have grown over their work and

Messrs. BAILLIÈRE, TINDALL, AND Cox have issued the fallen to decay, other generations of trees springing up. When

fifth edition of the “ Manual for the Physiological Laboratory,” ihe mines were rediscovered, decayed trunks of large trees were

hy V. D. Harris and D'Arcy Power. The work has been lying over the works, while a heavy growth of live timber stood enlarged, the increase being due mainly to the more detailed on the ground.

account which has been given, for junior students, of microThe last two parts of the Izvestia of the Russian Geograph- scopes and their properties; and to the description, for senior ical Society (vol. xxvii., 3 and 4) contain M. Grum-Grzimailo's students, of the latest methods of histological research. The report on his journey to Central Asia, and General Tillo's calcu- | parts relating to physiological chemistry have been thoroughly lations of the heights determined by the Russian traveller during revised, and many additional illustrations have been inserted. his journey. The report, which adds little to the information

MR. JAMES STIRLING, Assistant Government Geologist, given in the explorer's letters, is accompanied by a map em

Victoria, has published at Melbourne some valuable and bodying the results of the extensive surveys made by the two

interesting notes on the hydrology of the Mitta Mitta. The brothers in the Eastern Tian Shan, the Hashun Gobi, the Barkul

following are the leading conclusions to which he has been led oasis, and the region in the south-east of it, as far as the 36th by his observations :-(1) That there is considerable inequality degree of latitude and the 72nd degree of longitude. It was

in the amount of rainfall over different portions of the same already known that during this journey the brothers GrumGrzimailo had discovered, some filty miles to the south-east of watershed area in each of the various streams flowing from the Turfan, a depression situated between the two chains of the Australian Alps, the Mitta Mitta being cited as an instance of Eastern Tian Shan and the Kuruk-tag Mountains, the level of this; and that as the recording stations at present established

are all below the normal line of cloud flotation (under 4000 feet), which proved to be very near to the sea-level, or even below it. At the spot, Lukchin-chir, their barometer rose (on October in the several watershed areas is really greater than that shown

where the rainfall is greater, the actual quantity which falls 27) to 7717 mm. On the same day, the pressure of the in the records. (2) That the low percentage of discharge to atmosphere, reduced to the sea-level, attained 784 mm. at Kras, rainfall is due in all probability to a complexity of causes, among noyarsk, 787.7 mm. at Yeniseisk, 774 mm. at Irkutsk and which may be cited the excessive evaporation in certain areas, Tomsk, and 767 min. at Przevalsk and Narynsk ; so that there may be some doubt as to the pressure in the latitude and longi- largely due to the great range of temperature ; the different

heat-radiating powers of different rock-masses ; and percolatude of Lukchin-chir (at the sea-level) really being 767 mm., as

tion along fault lines, contacts of the igneous and sedimentary adopted by General Tillo, which would give for that spot 50 formations, &c.; and, in some areas, the absorption by cermetres below the level of the sea. But the possible error cannot be very great, and we thus have, between the two above-named

tain species of the prevailing eucalyptus vegetation. (3) To chains of mountains, an undoubted depression, the surface of ing its local distribution, it has become necessary to establish

determine the actual quantity of rainfall and the causes affectwhich is very near to the level of the ocean.

meteorological stations at the higher altitudes in the Australian MR. L. STEJNEGER describes, in the Proceedings of the Alps. (4) And in order to supply further trustworthy data, it American National Museum, a new North American lizard of is, Mr. Stirling thinks, imperative that a system of complete the genus Sauromalus. It is very large, the total length of four topographical survey should be instituted. specimens averaging 540 millimetres. This enormous lizard is closely allied to the much smaller species which inhabits the arid

The Annual Report, for 1888-89, of the Geological and regions of the mainland to the north of the Gulf of California,

Natural History Survey of Canada has been issued. It forms viz, Sauromalus ater, with which it has been confounded. It

the fourth volume of the new series, and includes reports and

maps of various investigations and surveys. The volume opens may be readily distinguished by the characters given in Mr. Stejneger's diagnosis.

with summary reports, by Mr. Alfred R. C. Selwyn, the Director,

on the operations of the Geological Survey for the year 1889. Some time ago the Educational Museum of Tokyo was Then come the following reports :-On a portion of the west abolished, and the collections were transferred to the Science Kootanie district, British Columbia, by G. M. Dawson ; an College of the Imperial University. Dr. I. Ijima, Professor of exploration in the Yukon and Mackenzie basins, by R. G. Embryology and Comparative Anatomy, who volunteered to McConnell; exploration of the glacial Lake Agassiz in Manitoba, by Warren Upham; the mineral resources of the province of black substance is found, which appears to consist of a lower Quebec, by R. W. Ells ; the surface geology of Southern New sulphide of the composition B.S. The same substance is obBrunswick, by R. Chambers; chemical contributions to the tained when the trisulpbide is heated in a current of hydrogen ; geology of Canada from the laboratory of the Survey, by G. C. a portion volatilizes, and is deposited again further along the Hoffmann ; mining and mineral statistics of Canada, by H. P. tube, while the residue suses, and becomes reduced to the unalBrumell; division of mineral statistics and mines, by E. D. terable subsulphide B.S, sulphuretted hydrogen passing away in Ingall and H. P. Brumell ; annotated list of the minerals

the stream of gas. occurring in Canada, by G. C. Hoffmann.

Two selenides of boron, B,Sez and B,Se, cori

corresponding to The administration of forests seems to be, on the whole, one the above-described sulphides, have also been prepared by M. of the most satisfactory departments of public activity in India. Sabatier, by heating amorphous boron in a stream of hydrogen Dr. Ribbentrop, in his report for the year 1889-90, states that selenide, H,Se. The triselenide is less volatile than the triover 4200 square miles were added to the area of forest estates sulphide, and is pale green in colour. It is energetically de. under control, thus bringing the total area up to nearly 105,500 composed by water, with formation of boric acid and liberation square miles. The gross revenue exceeded 153 lakhs of rupees, of hydrogen selenide. The liquid rapidly deposits free selenium, giving a surplus over expenditure of nearly 73 lakhs, or an owing to the oxidation of the hydrogen selenide retained in increase in a single year of 15 lakhs. The surplus in 1885 was solution. Light appears to decompose the triselenide into free only 41 lakhs. It is believed that this rate of increase may be selenium and the subselenide B.Se. maintained, as the rich forests of Upper Burma have still to be opened out.

SILICON SELENIDE, SiSen, has likewise been obtained by M.

Sabatier by heating crystalline silicon to redness in a current of In a recent communication from Alta Verapaz, a department hydrogen selenide. It presents the appearance of a fused hard in Guatemala (Mit. Zeit.), Dr. Sapper describes the climate.

metallic mass incapable of volatilization. Water reacts most The position is on the north slope of a hill-range stretching east vigorously with it, producing silicic acid, and liberating hydrogen and west, and the large rainfall (it has a rainy season in winter, selenide.' Potash decomposes it with formation of a clear as well as that in summer common to the whole of Central solution, the silica being liberated in a form in which it is readily America) apparently affects the frequency of earthquakes. For dissolved by alkalies. Silicon selenide emits a very irritating the district is of limestone and dolomite, and honeycombed odour, due to the hydrogen selenide which is formed by its rewith caverns and subterranean watercourses, and heavy rains action with the moisture of the atmosphere. When heated to lead to a collapse of such cavities, so that towards the end of redness in the air it becomes converted into silicon dioxide and the summer rain season, and still more towards that of winter, free selenium. the number of earthquakes and tremors is distinctly increased. The winter of 1889-90 had unusually heavy rains, and the

The additions to the Zoological Society's Gardens during the earthquakes were also unusually numerous (seventeen in 1890 past week include a Macaque Monkey (Macacus cynomoigus 8) as against five the previous year).

from India, presented by Mr. G. E. Lidiard ; two Senegal

Touracous (Corythaix persa), a Madagascar Porphyrio (Porphyrio A PAPER upon the sulphides of boron is communicated by M. madagascariensis) from West Africa, presented by Mr. J. B. Paul Sabatier to the September number of the Bulletin de la

Elliott; a Blue-fronted Amazon (Chrysotis estiva) from Brazil, Société Chimique. Hitherto only one compound of boron with

presented by Mrs. H. R. Warmington; two Puff Adders sulphur has been known to us, the trisulphide, B.S3, and con- (Vipera arietans) from South Africa, presented by Messrs. cerning even that our information has been of the most incom

Herbert and Claude Beddington ; two Tree Boas (Corallus plete description. Berzelius obtained this substance in an

hortulanus) from St. Vincent, W.1., presented by H.E. the impure form by heating boron in sulphur vapour, but the first

Hon. Sir Walter F. Hely Hutchinson, K.C.M.G. ; a Tree Boa practical mode of its preparation in a state of tolerable purity (Corallus hortulanus) from Demerara, presented by Mr. J. J. was that employed by Wöhler and Deville. These chemists Quelch, C.M.Z.S. ; 'a Black-headed Lemur (Lemur brunneus), prepared it by allowing dry sulphuretted hydrogen gas to stream

from Madagascar, a Brown Capuchin (Cebus fatuellus) from over amorphous boron heated to redness. Subsequently a South America, a Black-headed Caique (Caica melanocephala) method of obtaining boron sulphide was proposed by Fremy, from Demerara, a Red and Blue Macaw (Ara macao) from according to which a mixture of boron trioxide, soot, and oil are

Central America, deposited ; a Black-headed Caique (Caica heated in a stream of the vapour of carbon bisulpbide. M. melanocephala) from Demerara, purchased. Sabatier finds that the best results are obtained by employing the method of Wöhler and Deville. The reaction between boron and sulphuretted hydrogen only commences at red heat,

OUR ASTRONOMICAL COLUMN. near the temperature of the softening of glass. When, how. ever, the tube containing the boron becomes raised to the

OUTBURST OF DARK SPOTS ON JUPITER.–Attention has

been called by several observers to a number of dark spots which temperature, boron sulphide condenses in the portion of the have appeared lately on the first belt north of the north equatube adjacent to the heated portion ; at first it is deposited in a torial belt of Jupiter, in about latitude 20° Mr. Denning state of fusion, and the globules on cooling present an opaline derived a period of rotation of gh. 49m. 27'2s. from his observaaspect. Further along the tube it is slowly deposited in a tions of one of these objects between August 21 and September porcelain-like form, while further still the sublimate of sulphide 15. (Observatory, October 1891). A change then occurred, for takes the form of brilliant acicular crystals. The crystals consis

this spot, and others near it, were found to have a rotation period

of gh. 49m. 44'2s. from September 15 to October 15. This of pure B,S: ; the vitreous modification, however, is usually sudden change of 17 seconds in the rate of motion of a region of contaminated with a little free sulphur. Very fine crystals of some extent is most remarkable. A series of photographs of the trisulphide may be obtained by heating a quantity of the Jupiter were taken at Lick Observatory in August, which, porcelain-like form to 300° at the botfom of a closed lube whose according to Mr. Stanley Williams, "are of such a degree of upper portion is cooled by water. The crystals are violently excellence that an examination of them is almost like looking at decomposed by water, yielding a clear solution of boric acid, graphs show six or seven dark spots, and a comparison of them

the planet itself” (Observatory, November 1891). These photosulphuretted hydrogen being evolved. On examining the porce- with a sketch made about one rotation later clearly indicates a lain boat in which the boron had been placed, a non volatile displacement of the spo:s with reference to the great red spot,

m. S.

Nov. 14

4 35 16

...

10'2

9 36 16

20

...

...

8:3

20

6.5

II

18 39

20

15 26

...

...

4'3

owing to the more rapid movement of the belt in which they planets can attain. In the last form the tabulation is so arranged occur. Prof. E. E. Barnard observed the spots so early as May last ihat the following numbers can be directly seen :-(1) The num(Astronomische Nachrichten, No. 3063). He found in September ber of oppositions in which, up to the present time, places have that they were decreasing their longitudes about 10° daily. At been found, with the number of appearances since observed. this rate they would describe a complete rotation round Jupiter, (2) The number of every known opposition in which the planet relative to the great red spot, in about 36 days. The daily loss has been observed. (3) Every planet to which the foregoing derived from Mr. Denning's observations in August and Sep- statement refers. (4) The number of these planets. tember would bring the two spots in conjunction in about 39 days.

Wolf's PerioDIC COMET.— The following ephemeris is from SOME EXPERIMENTS MADE WITH THE one given by Dr. Thraen in Astronomische Nachrichten, No. VIEW OF ASCERTAINING THE RATE OF 3064 :

PROPAGATION OF INDUCED MAGNETISM Ephemeris for Berlin Midnight.

IN IRON.
1891.

Right Ascension. Declination, Brightness.
h.

THE question, considered in a simple form, may be put thus : - 8 29 28

Suppose a magnet were suddenly brought up to one end of 17 33 27

a long iron rod, what length of time interyenes between the 31 31 10 36 44 93

occurrence of magnetization at the near end and at the far end ? 23 29 31 11 30 38

Everyone, probably, would at first be inclined to say that the 26 27 31 12 17 51

speed along the bar would undoubtedly be about the same as 29 25 31 12 58 22

the velocity of light, and this supposition would naturally follow Dec. 2 23 37 13 32 15 74

if the energy to places along the bar be supposed transmitted 21 48 13 59 40

through the surrounding space ; but, on the other hand, the 8 14 20 51

speed may be much less if the energy of magnetization is trans14 36 10

mitted from particle to particle in the iron-the orientation of 14 17 22 14 45 59 57

the molecular magnets being, as it were, passed from each to the 17 16 17 14 50 41

next along the bar. In such case we would, of course, expect 14 50 38

49

the velocity of propagation to be comparable in speed with that 23 14 49 14 46 14

of molecular phenomena rather than that of disturbances in 26 4 14 27 14 37 52

the ether. Although the comet is getting fainter and moving south, it

The velocity of sound, with which we may, perhaps, compare may probably be followed to the last date in the above ephe it, is in iron about 16,coo feet per second." The transmission meris with instruments of moderate aperture. The greatest

of sound resulting from vibratory movement can be said to desouthern declination of 14° 51'8" is reached on November 18.

pend on the mass of the molecule, and on the mutual forces

keeping the molecules in position; while the rate of propa. The Total LUNAR Eclipse of November 15.—If atmo

gation of a magnetic disturbance of the kind supposed would spheric circumstances permit, a total eclipse of the moon inay depend on the moment of inertia of the particles (assumed be observed over all Europe on Sunday next, November 15.

to be molecular magnets) round their axes of rotation, and on The following are the times of contact with the earth's shadow their mutual magnetic moments. given in the Nautical Almanac :

The propagation of such a disturbance can be observed in G.M.T.

Prof. Ewing's magnetic model. The model, which consists First contact with the penumbra

9 367 essentially of a great number of small compass needles placed shadow

10 35'1

within each other's action, but not near enough to touch, can be Beginning of total phase

II 374

disturbed at one place by bringing a magnet near, or otherwise. Middle of eclipse

12 18:9

The disturbance then is seen to spread throughout the model, End of total phase

13 04

much in the same manner as we have suggested a magnetizing Last contact with the shadow

14 27

disturbance to be propagated in iron. penumbra

15 I'!

The method proposed to test matters depended upon the The first contact with the shadow occurs at 55° from the most directions observed through the production of stationary waves.

principle of the interference of waves travelling in opposite northern point of the moon's limb counting towards the east, the last contact at 95" from the same point counting towards the each end, and if the same alternating current be passed through

Thus, if a bar of soft iron have two coils of wire placed one at west.

both coils, disturbance of opposite signs travelling in opposite THE ELEMENTS OF THE MINOR PLANETS.—The Viertel. directions along the bar should interfere, provided the rate of jahrschrift der Astronomischen Gesellschaft (first volume) con alternation and the length of the bar are chosen suitable to the tains two interesting compilations, on the planets discovered rate of propagation, in the year 1890, and on the appearances of comets in the It was proposed to detect the nodes or places of interference same year.

The first paper is contributed by Dr. Paul | by means of a telephone in circuit with a third coil which could Lehmann, and informs us that no less than fifteen new members be slid along the bar. of our minor planet system were discovered last year between Instead of employing two alternating coils, the bar can be bent February 20 and November 14. In the table that follows a round to form a ring, and one coil will be then sufficient. summary of all the days on which each individual planet was Some preliminary experiments with a straight bar having observed is given, and this is succeeded by another which shows given saint indications of the existence of places of minimum their chief elements. By combining the elements of some of intensity, closed magnetic circuits or rings, formed of a the old planets with those of the new ones, some striking com- great number of turns of soft iron wire, I were then tried binations are thus brought to light, of which we give the two with more decided results. When the alternating coil was following cases, in which the new planets are 292 and 288 :- certain positions on the ring the telephone coil could Planets.

be placed at points where no sound, or if any very slight, 152 8 = 41.3 i = 12:2

0 = 44 a = 3:15

could be heard-the sound reaching a maximum in places 432 16-5

50

2:58 somewhere between these points. These nodes and inter99 42'0 139

2.80 nodes occupied about half the ring—the opposite half of 155 43'1 14'1

2'90

the ring from that in which the alternating coil lay. On 292 43'1 147

24

2:53 approaching nearer the alternating coil, apparently the very

unequal length of the paths prevented any effect being observed. 268 8 = 121*7

i = 2.0

= 79

a = 3'09 It was without difficulty ascertained that these were not the 1216

44
116
275

* Two rings were made of No. 21 soft iron wire, one about 10 feet and the 113 123'1 5'0

2'38 50

other 14's feet in circumference. Both had 8 pounds of wire wound on. 213 122'4 6.8

The wire used in a third ring was No.32 This ring was about 12 feet in The next table shows the values that have been obtained after

circumference. There was about 4 miles of wire put on. The wire of this

and the 14-feet ring was well coated with shellac before winding, so as to computing the mean brightest and darkest magnitudes that the minimize Foucault currents.

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