of publication. Dr. Mill closes his volume with proposals for an international scheme of Antarctic research, to be undertaken with the help of an international committee, the functions of which he proposes should be advisory. He recommends the use of three or four whalers and light motor-cars, but no balloons, the uselessness of which has been twice proved. The actual organisation of the expeditions should be left to those responsible for the money, and he holds that "the price of a battleship would conquer all the secrets of the South, not without risk,

but still with far less risk than in say ten years of football." The book is illustrated with an excellent map of the Antarctic regions by Bartholomew, by many photographs of the scenery and ice-forms, and an excellent series of portraits of the chief actors in the Antarctic field. The frontispiece, an instructive picture of Antarctic ice, has been contributed by Prof. von Drygalski.

through the pack to the latitude of 70° 25' S., and though several times beset, it escaped and returned to the South Orkneys. Suitable winter quarters were found in Scotia Bay, on Laurie Island; a house and magnetic observatory were built ashore, and the winter spent in active work. On the return of spring sledging expeditions explored the island and determined the Ordovician age of its rocks by Dr. Pirie's discovery of Pleurograptus and Discinocaris in the slates of Graptolite Island.

As soon as the Scotia could be freed from the ice it sailed for Buenos Aires for stores, &c., while Mr. Mossman, with five men, remained at the station to continue the meteorological work. The Scotia returned on February 14, bringing with it a party of observers sent by the Argentine Government, which had wisely undertaken to maintain the meteorological station; Mr. Mossman remained to help the Argentine party during its first winter, and the

The latest original contribution to Antarctic literature is "The Voyage of the Scotia," the narrative of the Scottish National Antarctic Expedition. The expedition was organised and commanded by Mr. W. S. Bruce, who after a voyage to the Antarctic in a Dundee whaler in 1892-3 had persistently advocated the despatch of an expedition to the Weddell Sea, and by careful training had rendered himself fit for its command. He had made several visits to the Arctic, and from 1894 to 1896 had been in charge of the Ben Nevis Observatory, so that he was an expert in meteorological observation. The funds available for the expedition were comparatively small, and were mainly due to the generosity of Mr. Jas. Coats, of Paisley. The expedition left the Clyde on November 2, 1902, and the Falkland Islands on January 26, 1903. It was already late in the season, and the ice appears that summer to have been unusually thick in the Weddell Sea; but the Scotia, commanded by an experienced Arctic navigator, forced its way

Scotia left on February 21 with the rest of the Scotch expedition for its second cruise in the Weddell Sea. Here the expedition achieved its two great geographical successes. It discovered a new land, Coats Land, which, judging from the boulders dredged off it, is composed of continental rocks, granite, gneiss, schist, sandstone, slate, and limestone. This land is probably the edge of Antarctica, which therefore occurs 400 miles farther north than the position suggested for it on Sir John Murray's sketch map. Murray had extended the Weddell Sea thus far to the south, as the natural inference from the reported soundings, which had been greatly exaggerated by Ross's primitive appliances. Where Ross reported no bottom at 4000 fathoms, the Scotia found blue mud at the depth of only 2660 fathoms. The Scotia has removed Ross's Deep from the chart. During the return voyage the Scotia visited Gough Island, which was found to be volcanic, and after calling at Cape Town, Saldanha Bay, and various

Atlantic islands, it arrived back in the Clyde in July, 1904.

The narrative of the expedition is told by three members of the staff, Mr. R. C. Mossman, the meteorologist and magnetic observer; Dr. J. H. H. Pirie, the medical officer and geologist; and Mr. R. N. Rudmose Brown, the botanist. Each author contributes the chapters describing the work with which he was most concerned. The book perhaps suffers as literature from the difference in treatment of successive chapters, but it has the advantage of describing the whole expedition by the first-hand accounts of men concerned in all the different sections of the work.

The narrative is of great interest. It tells the story of long, thoughtful preparation, of the setting forth of a band of determined men, each well trained in his own line of work, and of their quiet, successful achievement of their purpose. The expedition must be regarded, especially in view of its low cost, as remarkably successful. Its discovery of Coats Land

which affords grounds for hoping that the problem of syntonic signalling is at last nearing practical solution.

Mr. Poulsen will be familiar to readers of NATURE as the inventor of the telegraphone (see NATURE, vol. lxii., p. 371, and vol. lxiv., p. 183). Before describing the experiments shown at the Queen's Hall, it will be advisable to give a short account of the principles on which the new method is based. It has often been pointed out. in NATURE that all attempts hitherto made with regard to selective signalling are of a very unsatisfactory nature, and it has been suggested (NATURE, vol. lxviii., p. 249) that the solution is likely to be found in the application of the principle discovered by Mr. Duddell in the musical or singing arc. It is precisely that principle that Mr. Poulsen has adopted. The reason for this is sufficiently clear when it is considered that syntony, or tuning between transmitter and receiver, means the emission by the transmitter of sustained vibrations of definite frequency. Only when these are produced is it possible to employ in the receiver a circuit tuned or resonating to this particular frequency. The main difficulty with all methods of spark transmission is to produce these sustained vibrations. The signal produced by a spark discharge consists of a series of violent pulses each consisting of a short train of strongly damped vibrations of definite frequency. Such tuning as can be done is accomplished by making the natural period of vibration of the receiving circuit the same as the vibration period of the individual pulses, but as the effect of the pulse itself as such is práctically as great as that of its component vibrations, it will be readily seen that the tuning is only partial. To make the syntonisation effectual, the effect of the pulse must be diminished and that of the vibrations increased. In order to do this, the damping of the vibrations must be lessened until the signal is no longer a series of rapidly damped waves, but becomes a continuous succession of undamped, or, at the worst, very slightly damped vibrations, and the culminative effect of the continuous succession of waves will be far greater.

determined the hitherto quite unknown southern limit | of the Weddell Sea, and has broken the longest unknown line in the coast of Antarctica. As far as can be judged from published information, the Scotia will probably be found to have contributed more to Antarctic oceanography and biology than any of the expeditions in the field at the same time. Its deepsea equipment was excellent, and was fully used, and the description of the quantities of material obtained in the deep-sea hauls justifies the hope that the biological collections will yield most important contributions to our knowledge of the Antarctic fauna.

J. W. G.

SYNTONIC WIRELESS TELEGRAPHY.

ON Tuesday evening, at a reception given by Lord Armstrong at the Queen's Hall, Sir William H. Preece, K.C.B., F.R.S., being in the chair, a very important and interesting demonstration was given by Mr. Valdemar Poulsen before a large audience, which included, among others, H.R.H. the Duchess of Argyll, the Duke of Argyll, and the Danish Ambassador, of a new development of wireless telegraphy

arc

The problem, therefore, reduces itself to the production of a train of undamped waves, and the manner of its solution was indicated by Mr. Duddell when he discovered the phenomenon of the singing (NATURE, vol. lxiii., p. 182). Mr. Duddell showed that if a continuous current arc, burning under such conditions that a small rise in the current is attended by a small fall of potential-or in symbols for which dv/dA is negative and numerically greater than the resistance of the shunt circuit-is shunted by a circuit containing self-induction and capacity, there is spontaneously set up in that shunt circuit an alternating current the frequency of which is determined by the "natural" frequency of the circuit. By the use of

different inductions and capacities Mr. Duddell produced alternating currents of various frequencies causing the arc to emit a musical note. The frequency of these vibrations was, however, low-as is shown by the fact of the arc emitting a note—and in wireless telegraphy the frequency must be high. Mr. Poulsen has found that by burning the arc in an atmosphere containing hydrogen, by lengthening the

arc and by placing it in a strong magnetic field, the frequency can be enormously increased, and as many as a million vibrations a second may be obtained. Mr. Poulsen also finds that it is advantageous to have the anode of copper and the kathode of carbon, but when high currents are used the anode must be cooled by water running through tubes arranged for this

purpose.

Mr. Poulsen showed several interesting experiments, illustrating the delicacy of the receiving circuit, in that on the slightest variation of frequency the activity of the receiving circuit ceases. Another experiment with a generator the oscillation circuit of which was connected directly to a resonator the frequency o which was in agreement with that of the generator circuit (about one hundred and seventy thousand oscillations per second), showed stationary oscillations with maximum tension at the top of the coil, and gave a peculiar soundless flame. As indicating the enormous amount of energy produced, Mr. Poulsen showed several experiments-lighting six incandescent lamps which were simply connected to a coil of wire which was brought near the oscillation circuit; destruction of a copper ring of wire when brought near, &c.

Turning to the transmitter used by. Mr. Poulsen, there are two things of special interest, viz. the coupling and the signalling. As regards the coupling, the usual method employed is a very loose or close coupling, and the tuning is very sharp in either case. As regards the methods of signalling, various arrangements may be employed, but perhaps the most simple is by causing the key to short circuit a resistance periodically, which resistance must be large enough to reduce the amplitude and be included in the antenna-circuit. This method reduces sparking and permits of quick telegraphing. One may also telegraph by varying the tension of the magnetic field or of the feeding current, or altering the amount of hydrogen round the arc.

The receiving circuit for continuous waves includes an oscillation circuit with the least possible damping

and in loose connection with the antenna-circuit.

Owing to the continuity of the waves the detector may be arranged in such a way that it only intermittently forms part of the circuit of oscillation. Hence damping is avoided which the permanent in

The ap

clusion of the detector would introduce. paratus which causes the intermittent contact is known as the "Ticker," and the usual material used for the contacts is either gold wire or German silver. Mr. Poulsen claims to be able to tune in practice to one per cent., and has received three messages simultaneously without mutual interference, the difference of wave-length in this instance amounting to three

per cent.

Under the new method of undamped continuous waves Mr. Poulsen has sent a message from Lyngby, near Copenhagen, to North Shields, a distance of 530 miles, with a pole only 100 feet in height, for the expenditure of one kilowatt, and he hopes from this shortly to be able to get perfect communication across the Atlantic.

The chief advantages of Mr. Poulsen's system appear, therefore, to be:-(a) Extreme accuracy of tuning-thus ensuring selective signalling with no interference. (b) Freedom from interferences due to atmospheric electricity. (c) Greater efficiency due to accuracy of tuning and to the low potential of the electric surges impressed upon the aërial radiator.

Mr. Poulsen hopes that undamped and continuous wave-trains may yet be adapted to wireless telephony. The demonstration certainly proved that a great advance has been made in wireless telegraphy, and should the methods employed be brought into regular commercial use, there can be little doubt that Sir!

66 death

W. H. Preece's remark that probably the knell" of spark telegraphy has been sounded will prove to be an accomplished fact. In the first place syntony will become a really practical affair, and interference troubles between neighbouring stations, which have to a certain degree been responsible for the necessity of international legislation, will disappear. Secondly, the cost of transmission will be diminished, as with undamped oscillations the energy used in transmission can be enormously diminished. For the same reason the effective distance over which messages can be transmitted will be correspondingly increased, and we may hope to see the real establishment of that Transatlantic communication so often announced and so often abandoned.

J. L. M.

THE MARINE BIOLOGICAL ASSOCIATION AND INTERNATIONAL FISHERY INVESTIGATIONS.

LORD CARRINGTON, President of the Board of Agriculture and Fisheries, paid a visit to the Lowestoft Laboratory of the Marine Biological Association on Friday, November 23, in order to see the work which is being carried on at the laboratory in connection with the international fishery investigations in the North Sea. The principal features of the work were illustrated by means of a number of specimens and charts, which were explained by Dr. Garstang, the naturalist in charge of the laboratory, and by his assistants.

Hotel by the council of the Marine Biological AssoAfter being entertained at luncheon at the Royal ciation, Lord Carrington, who was accompanied by Mr. W. E. Archer, assistant secretary to the Board, visited the steam trawler Huxley, which carries out the investigations at sea.

Among those present to meet Lord Carrington were Mr. E. Beauchamp (M.P. for Lowestoft), the Mayor of Lowestoft, Mr. C. Hellyer (chairman of the

committee of the National Sea Fisheries Protection

Association), Mr. Deputy Sayer, of London, Mr. A. B. Capps and Mr. J. Jackman, of Lowestoft, and the following members of the council of the Marine Biological Association:-Dr. A. E. Shipley, F.R.S. (chairman), Prof. Bourne, Sir Charles Eliot, K.C.M.G., Dr. Harmer, F.R.S., Dr. Lister, F.R.S., Prof. D'Arcy Thompson, C.B., Dr. Chalmers Mitchell, F.R.S., Mr. G. L. Alward, Mr. J. A. Travers (treasurer of the association), and Dr. E. J. Allen (secretary and director), together with the members of the Lowestoft staff (Dr. W. Garstang, Mr. J. O. Borley, Dr. W. Wallace, Mr. R. A. Todd, and Mr.

A. E. Hefford).

Under the present arrangement the scheme of international investigations terminates in July, 1907, but the council of the Marine Biological Association, in view of the importance of the work already accomplished, is urging His Majesty's Government to continue similar researches upon a more permanent basis. In this connection the following statement of Majesty's Government :the views of the council has been forwarded to His

investigations extending over large areas are so great that it would be a decidedly retrograde policy that such cooperation should be abandoned. In support of the opinions expressed above, the council adduce the following statements and arguments with reference to sections (1) and (2) respectively, and believe that the statements will be fully substantiated in the detailed reports on the international investigations already published or in course of preparation. (1) In conformity with the main object of British participation in the international scheme of investigations, as explained in the House of Commons by Mr. Gerald Balfour on June 12, 1902, and in accordance with resolutions of the International Council at Copenhagen in July of the same year, the investigations carried out in the North Sea by the association, at the request of H.M. Government, have been largely concentrated upon the biological aspects of the undersized-fish question, especially as concerns the supply of plaice.

By means of nearly 1000 hauls of the trawl the sizes of the plaice in different parts of the southern North Sea have been determined in detail and mapped out for different seasons of the year. The measurements of plaice recorded at sea on the S.S. Huxley exceed a total of 100,000. These investigations have clearly revealed the distribution of the various sizes of plaice in the English area during the period of investigation, and have contributed extensive material towards the collective report on this subject which is in preparation by the International Committee.

The causes which influence this distribution have been carefully investigated with respect to (1) depth; (2) nature of sea-bottom; (3) character of the food-supply; (4) growth; age, sex, and maturity; (5) locality of the nursery and spawning grounds; (6) seasonal migrations; (7) density of fish-population; and (8) intensity of fishing; and on most of these points definite results have been obtained.

By means of experiments with more than 7000 marked plaice the migrations of this species have been plainly traced in important areas, and much progress has been made towards the explanation of the observed movements. The same experiments have furnished important results concerning the rate of growth in the chief parts of the English area.

An examination of the otoliths of more than 12,000 plaice caught and measured during the trawling investigations has yielded much new information concerning the age of plaice at different sizes on the chief fishing grounds, and has indicated a valuable method of controlling the results obtained from the marking experiments.

plaice of different sizes. Owing to the variety of the conditions which influence the experiments, it is not possible at present to express these results in a single set of figures representative of average conditions, but the experiments support the opinions (1) that under commercial conditions of trawling on the nursery grounds a large proportion of the small plaice taken are mortally injured, and would not live if returned to the sea, and (2) that the beam trawl is less injurious than the otter trawl under similar conditions.

With respect to other food-fishes, such as cod, haddock, sole, turbot, &c., a complete register has been kept of the catch of the large commercial trawls on every occasion (between 900 and 1000 hauls), and about 250,000 measurements, exclusive of those of plaice, have been recorded. The information thus acquired has laid a broad basis of exact and trustworthy knowledge concerning the general features of the fish-populations of different fishing grounds, and concerning the size, weight, and to some extent the rate of growth of the various species represented.

This information has been supplemented by more than 700 experiments with fine-meshed nets and dredges for determining the character of the sea-bottom itself, the dominant features of the bottom fauna, and the distribution of the fish eggs and fry which escape the commercial nets. In particular cases experiments have been carried out on the migrations and rate of growth of marked fishes, especially of cod, sole, lemon sole, and latchet, and the relation of size to age in the case of cod and sole has been studied to a certain extent by means of otoliths. Extensive observations have been made upon the food of many species in different localities, and concerning their relations to one another either as prey, competitors, or enemies.

With regard to the hydrographic and plankton investigations specified in the international programme, the association has fully carried out its obligations in this respect by the most thorough and painstaking investigation of the waters of the English Channel. The results have been regularly forwarded for incorporation in the quarterly charts and records issued by the Bureau of the International Council, and have been reported on from year to year.

(2) In view of the fact that special research has been mainly concentrated hitherto upon the plaice, and that other valuable species present points of practical importance which still await solution, especially the sole, turbot, cod, and haddock, it is very desirable that the investigations which have been begun on these species should be continued and developed.

regions. In the case of medium-sized plaice (10-15 inches in length), we have found that out of 1100 fish of this size liberated at various seasons of the year in the southern area, where sailing trawlers predominate, approximately 30 per cent. have been recaptured within one year from the date of liberation, and that out of 400 fish similarly set free on the Dogger Bank and adjacent grounds, where steam trawlers predominate, about 40 per cent. have been recaptured in the same period.

The council regard these results as of great significance from a practical, as well as a scientific, standpoint, especially as there is reason to believe that the figures understate the full severity of the fishing.

Other results derived from the marking experiments and otolith investigations throw new light on the relative mortality of the two sexes, their habits of seasonal segregation, and their relative susceptibility to capture by the trawl, points which bear directly upon the problem of the effects of trawling upon the economy, and therefore the supply, of this species.

By the transplantation of large numbers of small marked plaice from the coastal waters to the Dogger Bank and other grounds, it has been found, during two years in Succession, that the rate of growth is much greater on the Dogger Bank than on the nursery grounds, and the consideration of other factors renders it highly probable that the supply of fish can be profitably influenced by the transplantation of small plaice on a commercial scale. A number of special experiments have been carried out on the Huxley to determine the vitality of trawl-caught

necessity of scientific investigations has been generally recognised, whether such investigations be or be not carried out under a scheme of international cooperation.

While the council have indicated above the substantial progress which has been made with the experimental work at sea under their control during the past few years, they strongly urge that if this work should be brought to a sudden conclusion the prospective value of much preliminary labour and expense would be lost. Continuity of work is a factor of more than usual importance in experimental investigation of this character, not only because the conditions of the phenomena are constantly changing, but also because the extent and value of the results likely to be obtained are largely dependent on the experience of the staff employed.

NOTES.

M. MASCART is retiring from the position of director of the Central Bureau of Meteorology in Paris. He will be succeeded on January 1, 1907, by M. Angot.

MR. L. A. PERINGUEY has been appointed to the directorship of the South African Museum, Cape Town, to fill the vacancy caused by the resignation of Mr. W. L. Sclater. Mr. Peringuey, who has been assistant director for some years, is a well-known entomologist, and author of many papers on South African Coleoptera and other insects.

MADAME CURIE's opening lecture to the students attending the course in general physics at the Sorbonne on November 5, on the subject of "Les Théories modernes relatives à l'Électricité et à la Matière,' has been published in full in the issues of the Revue scientifique for November 17 and 24.

DR. E. SYMES-THOMPSON, Gresham professor of medicine, and an authority on pulmonary diseases, died on Saturday, November 24, at the age of sixty-nine.

SIR RICHARD FARRANT, who died on November 20, at seventy-one years of age, was treasurer of University College, London, which owes much to his business capacity. It was largely due to him that the fund was started to raise 200,000l. to provide for the necessary buildings and financial arrangements required for the incorporation of the college and the University of London, and his exertions in connection with the scheme will not readily be forgotten.

THE New Zealand International Exhibition was opened on November 1. The exhibits are valued at three-quarters of a million sterling, and two-thirds of this value represents industrial exhibits. The exhibition is the largest that has ever been held south of the equator.

THE winter meeting of the American Association for the Advancement of Science is to be held this year in New York City: The first general session will be opened at Columbia University on the morning of December 27. The president of the meeting will be Dr. W. H. Welch. The sectional meetings will begin in the afternoon of the same day, and in the evening Dr. C. M. Woodward, the retiring president, will deliver his address. The meetings will be continued on December 28 and 29, and if necessary on December 31.

VISITORS to the old Swedish cathedral and university town of Lund will find no little interest in the comparatively recent collections at the ethnographical museum illustrating many phases of rural life. Old peasant houses have been taken down, brought from considerable distances, and set up at Lund, among the buildings being an old church and an inn. Models of interiors of houses with costumed figures of inmates give an excellent idea of rustic conditions, reminding one, though on a smaller scale, of the Cecho-Slavonic museum in the Kinsky park at Prague. No catalogue of the collections has yet been issued.

IT is pleasing to note, from the current issue of its Bulletin, that the useful Société d'Encouragement, which is now in the 105th year of its existence, is in a satisfactory financial condition. After several years of deficit, the accounts for 1905 show a substantial excess of income over expenditure. The Bulletin contains useful summaries of recent progress in chemistry and mechanics, and affords clear evidence of the admirable work that is done by the society towards the development of the French national industries.

THE Home Secretary received at the Home Office on November 22 a deputation of members of the Royal Commission on Coal Supplies, who asked that the records and estimates which they have prepared at great cost to the country should be kept up by the Geological Survey to prevent their labours from being almost abortive. Lord Allerton believes that the whole of the information required could be had at a cost of 1000l. or 1500l. a year. Mr. Gladstone, while replying in sympathetic terms, pointed out that the Home Office is not properly equipped for

cooperating with the work suggested, and he is afraid there may be difficulty in obtaining monthly returns. Lord Allerton, however, thinks that the difficulty is exagger. ated, because, as chairman of a railway company, he has found that monthly returns can be obtained without increase of staff and without having to pay overtime.

IN connection with the fourth International Fishery Congress which is to meet in the City of Washington during September, 1908, a number of competitive awards has been arranged for the most important investigations, discoveries, or inventions during 1906, 1907, and 1908, relative to fisheries, agriculture, ichthyology, fish pathology, and related subjects. The awards will be in the form of sums of money varying in amount from 12l. to 5ol. The competition is open to any person, association, or company. Papers may be written in English, French, German, or Italian. The congress reserves the right to publish, prior to their publication elsewhere, any papers submitted in competition, whether such papers receive rewards or not. The awards will be announced at a session of the congress. All communications should be addressed to Mr. Hugh M. Smith, general secretary, United States Bureau of Fisheries, Washington, D.C., U.S.A.

steam

as

on

AT the Institution of Mechanical Engineers November 16 Mr. Thomas Clarkson read an interesting paper on a motive power for public-service vehicles. The advantages of steam for public-service work were summarised as follows:-the employment of a safe and cheap fuel; freedom from noise and vibration; absence of smell; and absence of change-speed gears, electric igni The maintenance cost of an tion, and friction clutch. engine that has been in regular public service on singledeck omnibuses for three years in Devonshire in 1905 was 6.23 pence per mile for total operating expenses, 1.5 pence per mile for tyres, and 1.16 pence per mile for depreciation. Much has been done towards obviating mechanical stops and breakdowns during the past two years, and the steam omnibus of to-day is shown by Mr. Clarkson to be a very satisfactory and trustworthy machine.

IN the first article of the fourth number of the Journal of Economic Biology (vol. i.) Prof. A. Nalepa, of Vienna, describes two eriophyids" (Acari) from Fiji. The first, Eriophyes hibisci, forms galls on a species of Hibiscus, of which the second, Oxypleurites bisetus, is also a denizen. In the second article Mr. G. H. Carpenter records the occurrence of larva of the chrysomelid beetle Psylliodes chrysocephala on Limerick. cabbage-plants at Much damage was done to the cabbages on which the larvæ fed, but the author is of opinion that the occurrence is an unusual one, and that the normal food-plant of the species is different. The third article is devoted to an account, by Mr. R. Newstead, of the life-history of the fly Stomoxys calcitrans, the larvæ of which are found in stables, cowsheds, &c.

IN vol. xvii. of L'Anthropologie appears an illustrated paper, by the late Mr. E. Piette, on evidence for the domestication or partial domestication of the horse (and possibly a wild ass) during the Reindeer epoch. This evidence consists of a number of sculptured and incised heads of horses invested with halters or head-stalls. Some of these headstalls, as shown in the figure of a head from the cave of St. Michel d'Arudy, are of a very complex nature, consisting not only of several strands of rope, but of a piece of buck's horn or bone under the lower jaw. The evidence seems to be conclusive as to the domestication of the horse