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from the Argentine Republic, presented by Mr. Hill; a Rough Terrapin (Clemmys punctularia) from Guiana, presented by Mr. J. J. Quelch, C. M.Z.S.; an American Milk Snake (Coluber eximius) from Tennessee, presented by Miss Winifred M. Middleton; a Virginian Eagle Owl (Bubo maximus) from South America, deposited; two Mouflons (Orlis musimon, ¿?) from Corsica, received in exchange.

OUR ASTRONOMICAL COLUMN.

THE NAUTICAL ALMANAC FOR 1896.-The new superintendent of the Nautical Almanac office has introduced a muchneeded reform into the first almanac, that for 1896, issued under his direction. The state of the British Nautical Almanac has long been severely criticised as being far from the best possible for navigational purposes both in form and contents, and by no means satisfactory from the astronomical standpoint. A letter addressed by the Shipmasters' Society to Dr. Hind, the late Superintendent, in November 1891, pointed out the advantage to navigators which would be offered by a work published at a popular price, and without that astronomical information which is of no use to sailors. Many low-priced almanacs are published, indistinctly printed, and having occasional errors in the figures, and an official trustworthy book was very desirable. In consequence of this representation the almanac is now published in two forms-as the complete almanac of former years, price 2s. 6d. ; and as Part I. of the Nautical Almanac, specially suited for the use of sailors, price Is.

The complete almanac has been revised and added to, many of the recommendations of the Nautical Almanac Committee of the Royal Astronomical Society, which reported to the Admiralty in 1891, having been adopted. The small short period terms of nutation have been tabulated, and, corresponding to that, additional day numbers are added so as to enable computers to include those small terms in the star corrections. The catalogue of stars from which the moon culminators and stars occulted by the moon are obtained has been revised and enlarged, and the mean places of the stars of this catalogue, which are used during the year, are also included. The elements of the occultations are given in a revised form similar to that adopted in most of the other astronomical ephemerides, so that the circumstances of an occultation for any position on the earth's surface can be computed with facility. There has been a general revision of the constants used.

The small almanac has been arranged by Mr. Downing in conference with the Hydrographer. As the guiding principle in publishing this was the minimum of change in the parts of the almanac which were to be extracted and published separately, there is still much in the volume that is not needed by sailors, but the omission of which would have necessitated the setting up of fresh type and much extra work at the Nautical Almanac office. The monthly part is printed unaltered, and consequently contains the sun's and moon's latitude and longitude, which are not required by sailors. The noon ephemerides for the brighter planets, Venus, Mars, Jupiter, and Saturn; the catalogue of mean places of stars, as well as the apparent places of the nine stars used for lunar distances; the eclipse section and the tables for navigation are then given. There is no doubt that the issue of this smaller work will confer a real benefit on the shipping community, and that it will soon win its way to popularity.

In announcing these changes to the Royal Astronomical Society, Mr. Downing expressed the hope of being able, through the economy of time effected by international co-operation in some of the work of the office, to make considerable future additions to the almanac without increasing the burden of the British taxpayer. The duplicate work done at Berlin, London, Paris, and Washington involves much waste of energy which might be more usefully expended: and as a step towards this, Mr. Downing, last summer, arranged with Prof. Newcomb, of Washington, to co-operate in some of the work of their respective almanacs, and the Admiralty have consented to this. It is to be hoped, in the interests of astronomy and of navigation, that the scheme may be greatly extended.

ECLIPSE PHOTOGRAPHY.-The results obtained by M. de la Baume Pluvinel at Salut Isles in 1889 (as given in his lecture which appeared in NATUKE last week), when he photographed the corona with photographic actions varying from 185 to 13, and found the photographic action of 30 the most satisfactory;

do not agree with those of the English expedition obtaine the same time and place. The photographic actions co plates exposed with the 20-inch mirror of 45-inches focus, b late Father Perry, varied from 1975 to 790 as calculate the formula given by M. de la Baume Pluvinel, and in pa case increase of photographic action gave greater exters the corona. Mr. Rooney's plates, with the 4-inch lens inches focus, had been subjected to photographic actions from III to 177'77, and agreed with Father Perry's it greater extension with every increase of photographic a The English results certainly justify the conclusion that photographic action is necessary to photograph those extensions of the corona which have been seen, but b hitherto eluded attempts to photograph them.

Mr. Burnham's experiments, alluded to by M. Plaval not assist us in this question. A certain absolute m light is necessary to give any appreciable photographic the plate, and this seems to be the chief difficulty in photographs of the external corona. In Mr. Bar experiments he had too much light and had to cut dow exposure in order to get faint contrasts, but there was neve question of not having sufficient light to obtain any photoga effect. Captain Abney finds (Phil. Trans. vol. di A 314) that an abrupt change of per cent. in the intensity a can be detected on a photograph, hence we may look negative as a drawing built up of 200 different shades exposure will of course prevent such faint contrasts as per being detected, and under exposure will enable fainte trasts to be seen, so long as the limit of minimum necessary to produce any photographic effect is passed, a evidence from the English expedition renders it ex probable that even with the largest photographic action or this limit was not actually reached with the faintest extes of the corona.

COMET HOLMES.-Dr. F. Cohn, writing about this 2 from the Observatory in Königsberg on January 17 (Astronomische Nachrichten, No. 3146), with a 6-inch her and a magnification of 65 times, that the nucleus is exa star of the 8th magnitude. The correction to the ephemers, below is, as he has deduced, Aa = 0.35., 48 = -6.

Dr. R. Schorr, of the Hamburg Observatory, puts the down on the same date as a 72 magnitude star with a nebulosity about it of 5" diameter, but on the 18th he f comet showed a much larger coma, a measurement gr The stellar nucleus was also estimated as 75 mag a diameter 2".

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gitude 72° west and latitude 17° north, between 11h. 48m. Sh. 48m. G.M.T., he deduced the radiant point from 70 t-track meteors, and four coincident stationary ones, giving position as R. A. 28°, decl. +36°. Counts being taken at rvals for areas of 60°, about 18 meteors per minute were reled, thus making a total number of 108 for the entire hemiere in one minute, or 6480 per hour. As this fall went on tinuously for six hours without any sign of the numbers inishing, we have the number of meteors 38,880, which Boraston says must certainly be a minimum, as many faint rapid ones must have escaped notice. A further observaat 8h. 48m. showed that the action was still being kept up, increasing this number to about 60,000. During this display as remarked that the meteors appeared much brighter when ant from the radiant point than in its vicinity.

NEW METHOD OF PHOTOGRAPHING THE CORONA.-M. Deslandres, in the Comptes Rendus of January 23, describes ethod of photographing the solar corona without the aid of rbing media. Sunlight is allowed to fall directly on a em of two identical prisms with parallel and inverted faces ed at a distance apart, such that only a portion of the

MAJOR LEVERSON, the British Commissioner for the delimitation of the frontier between the British South Africa Company's territory and the Portuguese possessions, has returned to this country, after having carried out extensive surveys and made considerable rectifications in the map of a strip of country stretching from the north-east corner of the Transvaal northward to Massikesse. The position of the latter point was fixed as 18° 15′ 33′′ S., 32° 51′ 24′′ E.

MR. MACKINDER gave the second lecture of his course on History and Geography, under the auspices of the Royal Geographical Society, on Friday evening, when he discussed the road to the Indies, showing how the desert route, which led to the growth of Palmyra, was superseded by the ocean route after the successful rounding of the Cape of Good Hope. The theatre of history in ancient times was the region enclosed between the pine forests of northern Asia and the Indian Ocean, divided into separate worlds by a double belt of deserts and steppes.

THE GROWTH OF ELECTRICAL INDUSTRY.

rging band from the first is intercepted by the second. ON Friday last Mr. W. H. Preece, F.R.S., delivered before r passing through the latter, the rays by recomposition give to a well-defined coloured image of the sun's disc. On lacing the prisms in a line perpendicular to the line joining ), the image assumes different colours, and on moving them git, the range of colours intercepted is made to change. prisms may be replaced by gratings. In a series of experis carried out during the autumn, nine successive impressions e sun's image were taken, ranging from the C line till far the ultra-violet. The object was to find the region where ight emitted by the corona showed the greatest photographic ence from that of the diffused sunlight in the atmosphere. matter of fact, a halo distinctly separated from the diffused ght showed itself on some of the negatives, especially in altra-violet region, which very probably represented the Ja. But to confirm this, simultaneous exposures at different, cially elevated, stations ought to be made, if possible g a total eclipse.

the Institution of Electrical Engineers his inaugural address as President. He said he had completed his fortieth year of continuous service in developing the practical applications of electricity for the use and convenience of man, and it appeared to him that he could not better repay the high compliment the Institution had conferred on him by electing him, for the second time, to be its President than by surveying and criticising the growth of the various branches of electrical industry with which he had been more or less associated during that long period. In the course of his address he dealt with telegraphy, submarine telegraphy, lightning protection, railway signalling, telephony, domestic applications, electro-chemical industry, electric lighting, power transmission, electric traction, and theoretical views of electricity.

GEOGRAPHICAL NOTES.

E February number of the Geographical Journal, in addio two important papers read before the Royal Geographical ty, and already reported in NATURE, contains a brilliant nt by Mr. Conway of the crossing of the Hispar Pass. views of mountain scenery were bewildering in their exfrom the foot of the valley an unbroken glacier was in stretching downward from the pass forty miles distant. unrivalled ice-stream was covered for the lower twenty with moraines. From the pass a vast snowfield, surrounded agnificent rock aiguilles, was seen to lie below, and from he Biafo glacier descended. From the end of the Hispar r to the end of the Biafo glacier was a distance of eighty , forming the longest snow-pass in the world outside the regions. Mr. Stephen Wheeler communicates a paper on ez Pinto, whose early travels in the East seem to have been y discredited.

is announced that the eminent geographical author M. Reclus has accepted a professorship in the University of els, and will commence his work there by a course of lecOn comparative geography.

ASTOR CHANLER'S expedition to Lake Rudolf, by the has reached Hameye, the Ibea Company's post at the of navigation on the Tana-a position accessible in five from the coast, to which camels, oxen, donkeys, and can be safely taken. Lieutenant Höhnel, who is atto the expedition, finds that Commander Dundas has the Tana from 20 to 22 minutes of longitude too far west, has searched in vain for the mountain ranges reported by

ers.

recent journey of some duration in the Sakalava plain in rth-west of Madagascar, M. Emile Gautier (according to nales Géographique) found the soil everywhere to consist ff red clay, weathered into steep-sided lumps and chasms ng sedimentary rocks, but quite similar in colour and er to the red clay which covers the volcanic rocks of the . M. Gautier believes that this clay is identical with the of the Deccan.

Speaking of telegraphy, Mr. Preece said :-The instrument that we have principally developed in England is the automatic fast-speed apparatus, based on a principle of preparing messages for transmission by punching, devised by Alexander Bain in 1848, and improved in its mechanical details by Mr. Augustus Ströh in 1866. This has been my special pet, and with the electrical assistance of Mr. J. B. Chapman, and the mechanical skill of Mr. J. W. Willmot, all the ills that telegraphs are heir to have been routed, and the practical speed of working has been multiplied more than six-fold. It has been one long continual contest between patient observation, inventive skill, careful experiment, and technical acquirement on the one hand, and resistance, electrostatic capacity, inertia (electro-magnetic and mechanical), bad insulation, impure materials, imperfect workmanship, &c., on the other. But we have, step by step, won all along the line: 75 words per minute have become 500; a possible 130 has become an actual 600. Duplex automatic working over cable lines is possible, and modes of working have been introduced that were thought at one time chimerical and impossible. . . .

The results to which I have referred have not been attained without very special attention to questions of construction and maintenance of the wires, both aerial and submarine, and a very complete system of test is now applied both before and after every line is completed. In the early days of telegraphic communication very rough and crude tests were applied, and the condition of the lines caused serious difficulties; but at the present day we must ascertain the purity of the metal employed, its mechanical strength, its electrical resistance and capacity, its insulation resistance, and the relationship between the latter and the conductor resistance, as well as its speed value. The employment of copper as the conductor suspended on poles in place of iron, which was inaugurated at my instigation in 1884, by a very costly experiment between London and Newcastle, has had a material influence in increasing the speed of working and improving telegraphy. This is due not only to its reduced resistance, but to the absence of electromagnetic inertia in a long, single-suspended copper wire. All our long important telegraphic circuits are now built with

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more rapidly by the British Post Office than by any private undertaking, and we have certainly shot ahead of our smart cousins on the other side of the Atlantic, from whom, however, I am proud to say, I learnt so much on my visits in 1877 and 1884. Their engineers are looking to us to develop their inventions, and we have done so. They cannot always get them taken up in the States. Diplex, quadruplex, and multiplex telegraphy are importations from them, but they have been improved in our service by our own developments, and have now become the staple and the standard modes of working. No one has done more to effect this object than Mr. M. Cooper.

An accident in the drafting of the Act of Parliament of 1868-69 transferring the telegraphs from the hands of private companies to that of the State, has led to a tremendous development of newspaper reporting in England. Few people are aware of the immense business done for the press. The growth of press messages is shown in the fact that 21,701,968 words paid for in 1871 have grown in 1891 to 600,409,000-an aver age of nearly 2,000,000 words per day.

When Mr. Gladstone spoke at Newcastle, at the National Liberal Federation, in 1891, 390, 778 words were signalled to different parts of the country. This kind of business is not, however, confined to the Post Office. The Exchange Telegraph Company, which commenced operations in 1872, working under the license of the Postmaster-General, has in London over 800 instruments at work (120 being in newspaper offices), distributing a daily average of 3,381,134 words to various receiving instruments adapted to the requirements of the respective services. The financial intelligence, for example, being transmitted over instruments furnished with type-wheels containing the various fractions most in use in Stock Exchange quotations. The latest form of this instrument prints at the rate of forty words per minute. General and parliamentary intelligence are distributed to the clubs over column printers, and legal, sporting, and Parliamentary news to newspapers on specially fast tape printers, capable of delivering, in the hands of skilled operators forty-five full words per minute to any number of subscribers simultaneously. The news transmitted is chiefly commercial and financial, amounting to 2,775,000 words per day.

To return to the purely State telegraphy. Some idea of the growth of the general telegraphic business of the country may be gathered from the following statement, which gives the total number of messages paid for in each year :

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In the course of his review of the history of submarine telegraphy, Mr. Preece said :-By far the greatest cable corporation in the world is the Eastern Telegraph Company, whose system of 25,376 miles stretches from Cornwall to Bombay, connects the northern and southern shores of the Mediterranean with Malta, and joins up the various other islands of the Mediterranean and the Levant. This company, in conjunction with the Eastern Extension and the Eastern and South African Companies, also gains access to Australia and New Zealand on the one hand, and to the Cape of Good Hope on the other, the combined mileage reaching a total of no less than 47,151. This enormous system has all grown up within, practically, the last 23 years.

The form of cable has practically remained unaltered since the original Calais cable was laid in 1851. Various sizes of core and armour, and various modes of protection from decay, have been used to suit different routes, but the cable of to-day may be said to be typically the same as that used in the English Channel in 1851, and in the Atlantic in 1865.

The first cable had gutta-percha as a dielectric, and it is still almost exclusively used for submarine cable core; but the manufacture has so improved in the last twenty years that a core having an insulator weighing 150 lbs. per naut, which then had a dielectric resistance of some 250 megohms a naut at 75° F., can now be obtained, giving 20co megohms at the same temperaIndiarubber is creeping in, owing to the high price and scarcity of gutta-percha.

ture.

Next to strong tides, rocky bottoms, anchors, and shallow water, the greatest enemy to submarine cables, more especially

in the tropics, has proved to be the teredo of various ge but this depredatory worm has been utterly routed by car the gutta-percha core with a lapping of thin brass tape i spirally. A remarkable thing about this little insects whereas twenty years ago it was practically unknown in English waters, it has now gradually spread all rom coasts, with the exception, perhaps, of the North Sea. A cable about to connect Scotland and Ireland is being with brass tape.

With the cables has grown up a fleet of telegraph ship and maintain them. In 1853 the Monarch, belonging Electric Telegraph Company, was the only ship perman employed as a repairing telegraph ship; now, in 1893, the fleet of the world numbers no less than 37, of which belong to Government administrations and the rest t companies, the Eastern Telegraph Company heading the with five vessels.

Perhaps the most remarkable history of a cable is the f ing-In 1859 the light cables laid in 1853 from Orforde Holland were picked up and replaced by a heavier one nauts were sold to the Isle of Man Telegraph Corp had an extra sheath laid on. This cable was submerged be that island and St. Bees, where it remained until 1885, OT was replaced by a three-core cable. It was again p water in 1886 as part of the cable between Uist and H the Hebrides, where it still lies, as good as ever. The bility of submarine cables is remarkable. That laid be Beachy Head and Dieppe in 1861 is still working; 25 laid between Beachy Head and Havre in 1870 has t within the last month for the first time.

Despite the enormous growth of submarine cables. these forty-two years, there would appear to be plenty for still further extension. The Pacific still remains untu and the project is at the present time under consider connect our possessions in North America with the Australia.

The following is the passage relating to telephony:-1 the good fortune in 1877 to bring to England the fire practical telephones. They had been given to me in Nes by Graham Bell himself. After a series of experie brought them before the British Association meeting was held that year at Plymouth. Who at that time col imagined that the instruments, which were then but toys within sixteen years, have become a necessity of comm and almost of domestic, life? Yet to-day the telephones in actual use may pretty safely be put das million !

During 1878 Edison devised his carbon transmitte Prof. Hughes presented his "microphone" to the These inventions made the telephone a practical instr vast commercial importance. It may be said to have into existence well-nigh perfect; and the fewness of th improvements on the Bell receiver and the Hughes nic is scarcely more astonishing than the immense number less attempts at improvement that have been made. Er the original instruments are not easily beaten.

The institution of telephone exchanges has led to 1 ment of systems of switching that might fairly be co special study in themselves, and the demand for comas between distant places has necessitated the application special attention to the method of constructing los arranging circuits.

It is in this latter field that I have heen a diligest and the application of the so-called "KR" law has p material benefit in connection with the problems of long telephony. It is a law which implies that the number that can be transmitted per second through any circa solely on the capacity (K) and the resistance (R) of the It is very much the fashion to deny the accuracy of the This is probably the result of ignorance of its meaning interpretation. Some speak of it as empirical, others as imaginary, and some sneer at it as an impossible -* it is a law that has determined the dimensions and working of all our long submarine cables; it determ number of arms a circuit can carry on the multiplex s speed attainable with the Wheatstone system, and t to which it is possible to work quadruplex; it is a law enabled us to bring London and Paris within clear" speech of each other, and which will probably before is out enable Dublin and Belfast to speak to Londor—2

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ace to Ireland as solid and substantial as any promised cal proposal.

New York and Chicago trunk line is 950 miles long, is built with 435 lbs. (or No. 8 S. W.G.) copper wire. wire gives a resistance of 206 ohms per mile, which is verified; but it is said by Mr. Wetzler to have a capacity 158 microfarad per mile, which cannot be verified, and is absurdly high. o'0158 microfarad was a measurement by me in England on an old line, but I have frequently d out that owing to the use of earth wires the capacity of nglish lines is very much greater than that of American Mr. Edison discovered this in 1872 when he came to nd to introduce his automatic system. Moreover, I have pointed out that induction still further diminishes capacity. The Paris circuit does not exceed o'005 arad per mile. I should estimate the Chicago circuit 04 microfarad per mile, and the KR at 7500, gives a result that quite accords with the opinions have heard expressed by those who have tried the two s as to the relative efficiency of the Paris and Chicago My American friends would have done better if they sed thicker wire. I should have specified 600 lbs. per but if it had been in England I should have used 1000 lbs., cannot dispense entirely with cables and underground is they have done in the States, and the increased capacity ced must be compensated for by reduced resistance. As er of fact, I once proposed 1200 lbs. wire for a circuit u London and Berlin-a distance of 760 miles, including 55 miles long.

beneficial effect of induction as a negative capacity is ed when working a circuit telegraphically with automatic eed apparatus. Thus, on two copper wires 450 miles aking 900 miles altogether, the speed on each single wire o words per minute, and on metallic circuit

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on same poles the improvement effected by induction was 25 per cent. e is no difficulty in measuring R of a metallic loop. The stone bridge determines it at onee. There is more diffi1 obtaining K. It cannot be measured directly. But metallic loop of copper, partly overhead and partly under, there are several modifications required, due to electroand electro-magnetic induction, which are at present the reach of formulæ, and render it difficult to determine acity except approximately from the telephonic effects Thus the capacity on the London-Paris circuit to be only one-half of that obtained by calculation, and ong circuit will require its own K to be determined by ison with an empirical K K scale. Such a scale I have ined by careful experiment on artificial cables.

ves.

re recently devised a new form of cable which will proquadruple the rate of telegraph working to America; nay say with all confidence that there is no theoretical whatever why we should not converse between London Ty capital in Europe, while it is not impossible to speak ross the Atlantic.

regard to electric lighting, Mr. Preece said that many are being made to utilise the waste forces of nature in ng electric currents for the economical supply of the In America, Scotland, Switzerland, Italy, and, indeed, er waterfalls are available, electric plant is being installed rt the energy of the fall into the useful form of electricity. li, near Rome, a fall of 165 feet is used to work six of 350 horse-power each, giving 2100 horse-power in ix high-pressure alternators working in parallel send I energy at over 5000 volts pressure to Porta Pia, near 148 miles from Tivoli, through four stranded copper ors, each having a diameter of 13mm., and bunched into allic loop, giving a total resistance of 4 ohms. At Porta 5000 volts are reduced to 2000, and the currents are disto several substations spread over the city, where they n lowered to the safe pressure of 102 volts, at which he current is supplied to the consumer on the three-wire There are 600 arcs and 30,000 glow lamps in use in but they are not all supplied from Tivoli. Mr. Preece d this installation only a few days ago, and found everyorking smoothly and efficiently under the able guidance Mengarini.

power abolishes the coal bill, but it must be remembered

that the cost of maintenance of machinery and of the erection and upkeep of conductors limits the distance to which the energy of falling water can be economically transmitted. The proposal to light New York by currents generated at Niagara is at present financially absurd. It is doubtful whether it will be commercially advantageous at Buffalo, 30 miles away, but it is certain that at Tivoli it can be so applied with advantage and profit.

There is much water power in this country that might be usefully employed. At Worcester it is proposed to use the water of the Teme, a tributary of the Severn, to supply electrical energy to the city-an experiment that will be watched with considerable interest, for the use of water power will solve the difficulty occasioned by light loads during the small hours and daylight. Keswick and Lynton have already been so served, but on a small scale only. There are many towns whose public streets could be brilliantly illuminated by the streams running past them, but there is much fear and distrust to be removed from the minds of our local magnates, and a considerable amount of education necessary before the public will receive the full value of the gifts that nature so freely places at its disposal, and the engineer so thoroughly converts into a utilitarian form.

The following are some extracts from the passage in which theoretical views of electricity are discussed :-

In the Presidential address which I delivered to the Society of Telegraph Engineers and Electricians in 1880, I took the opportunity to formulate the theoretical views of electricity that I had acquired at the feet of Faraday. It is not given to every boy to have his great ambitions realised. One of my ambitions as an earnest listener to Faraday's simple and delightful lectures was to be his assistant, and in almost the last investigation he undertook on electric induction in underground wires it was my privilege to see much of him, and to prepare many experiments for him. Early in 1854, at his wish, I carried out for Mr. Latimer Clerk certain experiments on the comparative effect of increments of voltage in increasing the rate of transmission of signals through long telegraph circuits. It was found that variation of voltage had no effect. Currents from 31 and from 500 cells sent through 768 miles of gutta-percha-covered underground wire showed precisely the same velocity. These experiments were sent by Faraday to Melloni, who had prompted the wish, and Melloni ("Faraday's Researches," vol. iii. page 577) remarked: "The equal velocity of currents of various tensions offers a fine argument in favour of the opinion of those who suppose the electric current to be analogous to the vibrations of air under the action of sonorous bodies." This is to be found in the very last contribution inserted in the greatest work ever published on our science, "Faraday's Experimental Researches in Electricity."

Faraday's views were subsequently expounded and extended by Maxwell, who said: "Faraday, in his mind's eye, saw lines of force traversing all space, where the mathematician saw centres of force attracting at a distance; Faraday saw a medium where they saw nothing but distance; Faraday sought the seat of the phenomena in real actions going on in the medium, they were satisfied that they had found it in a power of action at a distance impressed on the electric fluids" (Maxwell, Electricity," vol. i. page 10).

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Since that period I have never regarded electricity as anything else but as a form of energy, and its effects as modes of motion of the molecules of matter and of the ether that fills all space; and during my long apprenticeship of forty years I have never examined one experiment or considered one fact that was not explicable on this theory.

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Electricity is energy which is transmitted by matter and through space by certain disturbances the result and the equivalent of work done, and in certain orderly and law regulated forms, called "electro magnetic waves. It is not difficult to conceive the ether carved or the molecules of matter swayed or excited in definite periodic waves. molecule is subject to all kinds of motion-translation, oscillation, rotation upon its own axis, and revolution about some external axis. Clausius (Pogg. Ann., clvi. p. 618) suggested that the atoms or groups of atoms constituting a molecule revolve around one another similarly to planets, and are sometimes nearer to and sometimes further from each other. The difference between the infinitely great and the infinitely little is only one of degree. The motions of the solar system and that of a molecule of water are similar. These motions are imparted to and transmitted by

the ether, and they are taken up again by matter. One kind of wave gives us light, another radiant heat, another magnetism, and another electrification. The rate at which these waves move is the same, viz. 30,000,000,000 centimetres, or 192,000 miles, per second. It is only their form and their frequency that differ. Matter and ether are subject to strains, currents, vortices, and undulations, and every single electro-magnetic phenomenon can be compounded of or reduced to one or other of these mechanical disturbances. Rotation in one direction gives positive electrification: rotation in the opposite direction gives negative electrification. A whirl in one direction gives us north magnetism; in another direction, south magnetism. Hertz, the experimental exponent of Maxwell's views, bas shown the existence of electro-magnetic waves, and has proved their reflection, refraction, and interference. The rate of their propagation is the same in ether, air, and conducting wires.

The most recent discoveries and deductions are all in accordance with this mechanical theory. J. J. Thomson's views that at high temperatures, in the act of dissociation, all gases, and Dewar and Fleming's conclusion that at low temperatures-in fact, at the absolute zero of temperature-all metals become perfect conductors, might almost have been predicted. Hysteresis and Foucault losses are mere wastes of energy, due to molecular friction or to internal work done on the molecules, assisted by bad design and impure material; but, being measurable and comprehensible, their reduction to a minimum has become possible and actual.

It is a misfortune that a beautiful hypothesis like Maxwell's electro-magnetic theory of light has been discussed almost solely by mathematicians. Its consideration has been confined to a small and exclusive class. It has not reached the public; and this is to be regretted, for, after all, it is the many, and not the few, that determine the acceptance or refusal of a theory. The existence of the ether is now thoroughly comprehensible. Light is now regarded as an electro-magnetic disturbance. The eye is an extremely sensitive and delicate electro-magnetic instrument. The difference between luminous, thermic, and electro-magnetic waves is one of frequency and form. We thus have to consider the propagation of these waves not only in the conductor and in the dielectric in the direction of the circuit itself, but in the ether at right angles to this direction. The former produces currents in the conductor, and the latter induction and secondary effects in contiguous conductors. Thus it is easy to see why electric and magnetic lines of force are at right angles to each other, and each of them perpendicular to the line of propagation of the primary electro-magnetic wave, and why the transversal disturbances are secondary waves of electro-magnetic energy which can be transformed into electric currents of opposite direction whenever contiguous conductors lie in their path so as to be cut by these lines of force in the proper direction. Induction is thus mere transformation of energy whose direction and magnitude are easily calculated.

It is by following out this line of thought that I have recently succeeded in sending messages by Morse signals across the Bristol Channel between Lavernock and Flat Holm, a distance of 31 miles. The electro-magnetic disturbances were excited by primary alternating currents in a copper wire, 1237 yards long, erected on poles along the top of the cliff on the mainland. The radiant electro-magnetic energy was transformed into currents again in a secondary circuit, 610 yards long, laid along the island. The strength of these secondary induced currents complied almost exactly with calculations. The results attained, the apparatus used, the precautions taken to separate effects of induction from effects of conduction; the elimination of mere earth currents from electromagnetic disturbances in air, will form the subject of a separate paper, for their prop er consideration would be too tedious for an address. I allude to them now only to illustrate the existence of one of the greatest proofs of the truth of a theory, viz. the practical development and verification of a conclusion predicted from mere theoretical considerations.

The o-cillatory character of the discharge of a Leyden jar, which was discovered by Henry in 1842, is an admirable proof of this molecular theory. If two jars, precisely similar as regards capacity and circuit inertia, be placed near each other with their planes parallel, and one of them is charged and discharged, the other responds sympathetically, as do two similarly pitched tuning-forks when one is excited. Professor Oliver Lodge, who has made this field his own, has shown that by varying the capacity of the jars and the inertia of the circuit,

oscillations can be produced to give any required rate diet tion from one to 300 millions per second.

In a room or theatre, when these discharges are excited a common thing to see sympathetic sparks upon the g walls, and among the metallic objects scattered about whole place is an electric field, which is violently distri every spark, and everything which is "syntonised, as Lodge calls it, to the main discharge, responds in this way It is impossible to account for these effects, which are of transformed kinetic energy, except on the mechanical which I have advanced. We have a source of disturbe have energy transmitted in waves, we have wave transi into disturbance again. Energy passes through its various by the motion of matter and the action of the ether. thing is accounted for and nothing is lost. means energy in the wrong place.

Waste energy

YEZO AND THE AINU.

TWO papers on recent travels in the Island of Yezo we

to the Royal Geographical Society on Monday ev Prof. J. Milne, F. R.S., whose paper was read by the Sem made a journey to the north-east of the island by sea in 18 returned by land, crossing Yezo almost through its cente was accompanied by Mr. John Revilliod, and travelle view to studying the volcanic geology of the regions. La Kushiro, interesting on account of the relics of pre-Ar ants, and on account of its coal mines, they ascended the river to Shibecha, where there is a great convict pr sulphur refinery, the raw sulphur being obtained from th cano Atosanobori, to which there is a railway twenty s In this locality the violence of the escape of steam from ing springs exceeds anything seen elsewhere in Jap Zealand, or Iceland. A new road, thirty-seven miles it, from the volcano to Apashiri, on the north-east coast, factory for making matches has recently been erected, on of the abundance of the white-stemmed poplar, the which is much more readily worked in the fresh state th dried. A boat journey was made in a small dug-out c rugged cliffs from 500 feet to 1000 feet in height, for th to Shiritoki, where there is a great sulphur mine. Fr of the volcanic craters fused sulphur flows like lava, m lises in an almost pure state. A trip from Nemuro to the Kurile Islands was followed by the main feature of the a ride from Yubets, on the north coast, up the Yates across the watershed, and down the Ishikari river, 1997 coast. Groups of convicts working on the new roads being made across the island, were almost the only p with. Vast groves of tall bamboo grass everywhere the travellers, and insects of all kinds proved very tro There was little or no sign of larger animal life.

Mr. A. H. Savage Landor also read a paper. wandered all round Yezo and up several of the larg quite alone, and with no object save curiosity and the study the Ainu at home. The main part of his equi a great store of painting material, of which he made in portraying both the natives and the scenery of t The Ainu accessible from Hakodate, who have been visited and often described, are almost all Japanese ha and much influenced in customs and costume by ther neighbours. The Ainu of the interior and the parts of the coast were very different. The true Air are intensely filthy, and the vermin in them make unsupportable to a stranger, minute black flies, whic incredible hosts, being the worst. The people, alth humoured, are sunk in the most degraded savage marriage customs seem to be summed up is promiscuity, the Ainu disclaiming any idea of being bears or dogs. The Ainu language is poor in many of them show a curious resemblance to words Saxon origin, e.g. Chip, for ship; Do, day; Mas Pone, bone; Ru, road; To, two; Wakka, water. The beliefs of the Ainu can hardly be dignified by such i are merely superstitions. In travelling along the coast there was often considerable danger from washing over the narrow track which wound be boulders on the beach. Fog prevails along the ca summer, probably on account of the Kuro-Siwo en.. cold current off the island. The upper Tokachine

T

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