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rausch type (the crystal being immersed in a specially made tank containing a highly refractive liquid), and as a refractometer by the prism method (the telescope being removed and attached to the graduated circle, and the crystal-holder transferred to the rod used for bearing the tanktable).

It is obvious that in the case of a goniometer with a single circle only one zone of a crystal can be measured at a time. The difficulty of measuring with such an instrument a small, many-faced crystal is consequently very great, and there is grave risk of mistakes being made owing to tiny faces of similar appearance being confused. W. H. Miller, when measuring a complex crystal aggregate in 1874, was the first to recognise the advantage of defining the position of each face on a crystal by a pair of angular co-ordinates

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analogous to the latitude and longitude of a place on the earth's surface-in the case of a crystal it is, however, more convenient to make the pole the origin of measurements-and thus avoiding the necessity of altering the adjustment of the crystal, at least during the measurement of one half of it. In this method a goniometer with two circles mutually at right angles is required. Miller merely clamped one goniometer with a vertical circle on to another with a horizontal circle; a brief description of the instrument was given in a posthumous paper (published in 1882 by his successor, Prof. W. J. Lewis, F.R.S.), but attracted little attention. Instruments on similar principles were designed by E. S. Fedorov in 1889, and V. Goldschmidt in 1893. A different pattern, in which the optical parts are movable about a horizontal axis, was designed by S. Czapski in 1893. F. Stöber in 1898 described a

simple piece of apparatus consisting of a graduated circle, to which a crystal-holder was attached radially, for replacing the ordinary crystal-holder of the one-circle goniometer. This attachment has the inconvenience that in any position of the telescope the reflections from certain diametrically opposite parts of the crystal are obscured, and it is necessary to move the telescope through a measured angle; moreover, since the circle moves in so large a collar, accurate readings cannot be expected.

In the measurement of a crystal with a twocircle goniometer, if, as happens in the triclinic and sometimes in the monoclinic systems, a face of symmetry is not crystallographically possible at right angles to the edge of the zone of symmetry by which the crystal is adjusted, measurements are not made in zones, and consequently the most important property characterising crystals is not utilised. In any case the zonality of faces lying in or near cross zones cannot be directly tested on the instrument without readjustment of the crystal. The difficulty may be D overcome by the addition of a third circle, which is fixed at right angles to the second, and is inclinable at any angle to the first circle. A goniometer of this type was described in 1899 by G. F. H. Smith, and in 1900 by J. F. C. Klein. In the form designed by E. S. Fedorov, in 1900, the crystal has two motions about axes mutually at right angles in large semi-circular collars similar to the Stöber circle already mentioned. A threecircle goniometer with modified optical arrangements to allow of continuous measurements through half a revolution in any zone was designed by G. F. H. Smith in 1904. An instrument very similar to Fedorov's was described by V. M. Goldschmidt in 1912.

P

CHEMICAL FIRE-EXTIN

THE

GUISHERS.

HE article on "The Extincteur and its Limitations" in NATURE of June 3 described some practical points relating to the construction, tests, and use of portable fire-extinguishers now widely advertised and purchased. So much attention has been given to the article that a supplementary account of the chemistry of such extinguishers should be of equal interest and service. In putting out fire the chief things to be aimed at are the reduction of temperature and the exclusion of oxygen. Either will suffice if it can be obtained in a great enough degree, for combustion will not proceed if the temperature of the burning substance is lowered beyond a certain point; nor-apart from special cases with which we are not now concerned-can it take place in the absence of oxygen. In one class of the special preparations devised for use as fireextinguishers the two effects are usually combined; in another class the second effect is chiefly the means relied upon to secure extinction of the fire.

Water charged with carbon dioxide is the commonest example of the first class. The water

cools down the burning mass, and itself becomes heated in the process, whilst the carbon dioxide expelled from the water by the heat displaces the atmospheric oxygen in the immediate neighbourhood, and both causes combine to stop the combustion. The larger extinguishers such as are usually supplied to public buildings are of this kind. They contain, typically, a strong solution of sodium carbonate and a charge of hydrochloric or sulphuric acid. The acid is kept separated from the carbonate until the apparatus is wanted for use, when by means of a breaking or overturning device the acid is mixed with the solution, and immediately liberates the carbon dioxide. The pressure of the gas forces the solution out of the apparatus, just as in the action of an ordinary "syphon" of soda-water.

Other aqueous solutions, frequently used in small extinguishers of the hand grenade type, contain chlorides instead of carbon dioxide. Apart from the water, these are considered to act as fire-quenchers partly by producing extinctive gases, and partly by coating the burning material with a non-combustible film. One formula for such a grenade, for instance, contains common salt and sal-ammoniac, another includes calcium and sodium chlorides, others contain chlorides of calcium and magnesium. Of similar type, too, are some preparations containing sulphites. Thus a solution of sodium sulphite and sal-ammoniac acts as a fire-extinguisher partly by giving off ammonia and sulphur dioxide, partly by the cooling effect of the water, and partly by coating the burning material with sodium chloride.

Of these small extinguishers it may be said in general that for quenching incipient small fires indoors they are useful, but too much should not be expected of them. The quantity of solution in a single extinguisher, or in half a dozen, is too small to be effective unless the fire is of quite restricted dimensions. Much of the quenching effect, it must be borne in mind, is due to the water; and though the chemicals enhance this effect, they do not multiply it to an unlimited degree.

For use more particularly in putting out fires of burning liquids such as petrol, kerosene, and other mineral and vegetable oils, which float upon the surface of water and so may be spread by the latter, extinguishers containing dry powders are sold, and also others composed of non-aqueous liquids. The powders generally include carbonates or bicarbonates, with or without an admixture of chlorides. One much advertised article, for example, consists of a mixture of calcium carbonate and sodium bicarbonate. Their action depends chiefly upon the evolution of carbon dioxide and other gases, under the influence of heat. Like the hand grenade class, these extinguishers are in general effective only with small fires, and not in all circumstances. For example, a film of burning liquid might be extinguished readily by a covering of one of these powders, whereas the powder thrown on a thick

layer of the liquid might fall to the bottom and remain practically unaffected, at least until the oil had burnt down to its level.

Of the non-aqueous liquids employed the chie appear to be chlorinated hydrocarbons. They are probably mixtures of several members, ba: approximate more or less closely to tetrachloroethane, or to mixtures of this with carbor tetrachloride. These depend for their effect upoz the production of extinctive gases when heated, and one disadvantage of their employment is the evolution of fumes, copious and unpleasant, cosisting of hydrogen chloride. For use on small petrol fires, and also on small quantities of ignited inflammable materials, such as celluloid and carbon bisulphide, they appear to be reasonably efficacious. For larger fires, especially of loose combustible substances such as straw, paper, shavings, and the like, they are of much less value. Extinguishers of this class have thus a special and limited usefulness rather than general applicability to ordinary conflagrations. In fact with these as with all extinguishers, it is well to remember that whilst the prompt application to a small incipient. fire may be effective, it is quite another matter when a big blaze has been allowed to develop.

E

WE

THE SURGERY OF THE WAR.

́E are familiar, by this time, with the saying that the War has brought "Listerism back for the treatment of our wounded. Not that the use of antiseptics had ever vanished out of practice: but the aseptic method-the sterilising, by heat, of almost every appliance of surgeryhad come into general use, and had been reckoned as a great improvement on the antiseptic method. It had seemed a safer, more natural, more scientific way of operating. And in civil practice it is, indeed, well-nigh perfect. It is "the ideal method." That is to say, it would be perfect if all surgeons, nurses, and patients were perfect. But it is not so simple as it sounds and some surgeons, perhaps, have so admired the pursuit of the ideal that they have been tempted to think of Lister's work as a mere "stage on the way to their own. Then came the War; and, at once, surgeons had to face a condition of wounds very different from the clean-cut incisions made in the formal operations at placid, well-appointed hospitals and nursinghomes over here. This overwhelming multitude of shell-wounds and shrapnel-wounds, infected right away with mud and sweat and particles of clothing, and with all the germs of heavily manured soil, must be disinfected, if that were possible, with antiseptics. Thus, there has been that return to the antiseptic method which Sir Rickman Godlee described, a few months ago, in his lecture at the Royal Institution.

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But this return to Listerism reminds us of Mme. de Staël's wise saying, "L'esprit humain fait progrès toujours, mais c'est progrès en spirale." If we are indeed back at Lister, we are back at a higher level. higher level. It is exactly half-a-century since he, in Glasgow, in 1865, first plugged the wound of

a compound fracture with a strip of linen soaked in coarse, impure, undiluted carbolic acid. What came of that experiment the world knows, and is not yet tired of knowing. But he could not then foresee the wealth of new discoveries which followed, incessantly, this first method of dealing with "germs of putrefaction." Least of all could he foresee the swift rise of bacteriology, its extension over the whole art and science of medicine and surgery, and its magnificent achievement of protective treatments, antitoxins, and vaccines. But he lived to see them, and to help to make them possible. We are likely to have in our hands, before many months, the final and authoritative record of his life and of his work. It will be a

book worth waiting for, and it will be, even in these hard times, a book worth buying.

Meanwhile, for all who love to read of surgery

-and who does not?-there are two admirable lectures by Keen of Philadelphia, entitled "Before and After Lister." They were given to the United States Army Medical School a few weeks ago, and are published in Science, June II and 18. They have much to say of military surgery, past and present, and they say it very well. There is also a very striking article in the Times of June 28, on "Wounds and Blood-poisoning," and on the present work of Sir Almroth Wright at Boulogne. The lectures and the article, between them, give us a good insight into the progrès en spirale of surgery, from 1865 to 1915.

NOTES.

It was announced on July 5 that Admiral of the Fleet Lord Fisher of Kilverstone had been appointed chairman of the Inventions Board established to assist the Admiralty in co-ordinating and encouraging scientific effort in relation to the requirements of the Naval Service. The arrangements for the organisation of the Board have now been completed. It will comprise :-(a) A Central Committee; (b) a Panel of Consultants composed of scientific experts who will advise the main Committee on questions referred to them. The Central Committee will consist of:Lord Fisher of Kilverstone, G.C.B., O.M. (president), Sir J. J. Thomson, O.M., F.R.S., Hon. Sir C. A. Parsons, K.C.B., F.R.S., Dr. G. T. Beilby, F.R.S. The Consulting Panel will comprise the following list, which will be added to from time to time as necessary-Prof. H. B. Baker, F.R.S., Prof. W. H. Bragg, F.R.S., Prof. H. C. H. Carpenter, Sir William Crookes, O.M., F.R.S., Mr. W. Duddell, F.R.S., Prof. Percy Frankland, F.R.S., Prof. Bertram Hopkinson, F.R.S., Sir Oliver Lodge, F.R.S., Prof. W. J. Pope, F.R.S., Sir Ernest Rutherford, F.R.S., Mr. G. Gerald Stoney, F.R.S., Hon. R. J. Strutt, F.R.S. The Board is accommodated temporarily in the Whitehall Rooms, Hotel Métropole, Whitehall Place, S.W., but at an early date (which will be announced in due course) it will be transferred to permanent offices at Victory House, Cockspur Street, S.W. Communications should be addressed to the secretary, Board of Invention and Research.

WE regret to announce the death in action on the western front, on Saturday, July 10, of Lieut. Ernest Lee, a young botanist of considerable promise, who had already published some excellent work, notably a paper in 1911 on leaf-fall. Lieut. Lee obtained a national scholarship in 1906, and while at the Royal College of Science, South Kensington, was both Marshall scholar and Forbes medallist. He was an associate of the Royal College of Science and a fellow of the Linnean Society. In 1910 he became assistant lecturer in the botanical department at the Birkbeck College, London, and in 1913 went to the University of Leeds as a lecturer in agricultural botany. He there became a member of the Leeds O.T.C., and obtained a commission in the Duke of Wellington's Regiment soon after war broke out. In the autumn of 1914 he married Miss H. S. Chambers, lecturer in botany at the Royal Holloway College. Lieut. Lee was killed instantaneously by a bullet while with his guns, and he will be greatly regretted by all who knew him or his work.

LAST week we recorded with regret the death, at the age of twenty-seven, of Mr. H. S. Bion, assistant superintendent of the Geological Survey of India. Mr. Bion was born in India, and was educated at the School for the Sons of Missionaries at Yvesdon House, Blackheath, and at University College, London. His university career was a distinguished one. In 1905 he obtained the university scholarship in geology, and in 1906 the Morris geological prize. In 1908 he took the degree of B.Sc. in the University of London, obtaining first-class honours in geology. In 1911 he was elected a fellow of the Geological Society. In February, 1911, he joined the Geological Survey of India, and in the following November he was appointed curator of the museum and lecturer in the Presidency College, Calcutta. His work in the field was chiefly in Burma and Kashmir, and he did particularly valuable work in the latter area, especially among the Carboniferous rocks. His marked ability, his unselfish character, and scientific enthusiasm, endeared him to all with whom he came in contact, and his untimely death is deeply regretted by his former teachers in this country, his colleagues of the Indian Survey, and his numerous friends.

By the death of Mr. R. W. Raper, fellow, vicepresident, and bursar of Trinity College, the University of Oxford has suffered a serious loss. For some time his health had been failing, but the news of his sudden decease has come as a shock to his friends in Oxford, who had seen him walking about as usual up to within a very recent period. Mr. Raper was one of the best known and most highly respected of Oxford residents. His services to his college were of great value. The combination of clear-headed business aptitude, firmness in action, and humorous but not unsympathetic methods of dealing with difficult situations made him an almost ideal college bursar. Countless undergraduates have good cause to remember his generous friendship and refined hospitality. As a promoter of public interests he did a great work, both in his University and in his paternal home at Malvern. Oxford holds in especial gratitude his

action in defending the top of Shotover Hill from enclosure. The preservation of beauty, whether in nature or in art, always found in him an enthusiastic champion.

HERBERT KYNASTON, whose death was recorded in our issue for July 15, was the son of the late Dr. Kynaston, Canon of Durham, and was born on July 19, 1868. He entered King's College, Cambridge, making a special study of geology, and securing a first class in part ii. of the Natural Sciences Tripos in 1891. He proceeded to examine the volcanic rocks of Old Red Sandstone age in the Cheviot Hills, and was appointed an assistant geologist to the Geological Survey (Scottish Branch) on May 3, 1895. His first official work lay among the Old Red Sandstone rocks of Lorne and Glencoe, and he made important contributions to the Memoirs on Mid-Argyll and the Oban and Dalmally districts. He resigned his post in January, 1903, to take up the difficult duties of director of the reconstituted Geological Survey of the Transvaal, and numerous members of the British Association will recall his kindly guidance during a memorable visit to South Africa in 1905. The first report under his auspices, that for 1903 (see NATURE, vol. lxxi., p. 53), contains a paper by him and his colleague, A. L. Hall, on diamond-bearing pipes and alluvial deposits. He described in later reports the Komati Poort coalfield and the tin-deposits of Waterberg, south of the Limpopo, and much of his work had to be carried on in advance of the mapping of the country. When, under the Union Government, the Geological Surveys of the provinces were united, Kynaston was selected as director, and he initiated the series of Memoirs of the Geological Survey of South Africa. His death at Pretoria on June 28, 1915, at the early age of forty-six, will be regretted as much in Scotland as in South Africa, and some of his observations on the Glencoe area are embodied in a memoir that is still passing through the press. One of his colleagues writes of him with simple feeling as a man who was "a true friend, of quiet disposition, but full of kindly humour and affection."

WE learn from Science that Dr. Viktor von Lang, emeritus professor of physics at Vienna, has been elected president of the Vienna Academy of Sciences. The academy has elected as corresponding members Dr. Sven Hedin, Dr. Max Planck, professor of mathematical physics at Berlin, and Dr. P. H. von Groth, professor of mineralogy at Munich.

THE Livingstone gold medal of the Royal Scottish Geographical Society has been awarded to Lord Kitchener in recognition of his work on the survey of Palestine, and as a director of the survey of Cyprus, as well as in recognition of his signal services to the State. The society's gold medal has been awarded to Dr. J. Scott Keltie, late secretary of the Royal Geographical Society, in consideration of his services to geographical science.

WE regret to record the death on June 18 of Mr. T. D. West, at Glenville Hospital, Cleveland, Ohio. Engineering for July 16 contains a brief account of his career. Mr. West was born in Manchester in 1851;

his parents emigrated to the United States when te was an infant. He entered a foundry at the age of twelve, and was connected with foundry work throughout his life; he was a recognised authority on subjects pertaining to foundry work. At the time of his death he was chairman of the West Steel Casting Co., Cleveland. He was a member of several American societies, and was the author of several books and pamphlets on foundry practice.

THE annual meeting of the general committee of the Imperial Cancer Research Fund was held on Tuesday, July 20, Sir William Church in the chair. The work of the fund has been greatly curtailed owing to the war, and the scientific part of the annual report is restricted to a summary of the work pub. lished during the year. The work comprises an experimental study of metastasis, which emphasises the importance of the processes at the site of arrest of tumour emboli, an investigation into immunity to transplanted sarcomata extending the well-known findings with regard to carcinoma to the connective tissue tumours, and biochemical studies. The two biochemical papers deal with the action of ferments. The first is concerned with the effect of minute alterations in the reaction of the medium on the activity of a maltose hydrolysing ferment. The second deals with the action of the protein-splitting ferment present in normal serum of man and animals as accounting for the phenomena comprised in the Abderhalden serum reaction. The conclusion is drawn that the doctrine of specific protective ferments set up by Abderhalden is unsound, and that the reaction even in its improved form cannot be relied on for the serumdiagnosis of pregnancy or cancer. The report also discusses the pathological bearings of the new and interesting data in the Registrar-General's Report for 1913 on the influence of marital condition in women on the mortality from cancer of organs special to their sex.

interesting article on war orders and their effects on THE Engineering Magazine for July contains an American industry. Sales of benzol have been much stimulated by the war, and the price has been quintupled. American makers of explosives have had two problems to solve, first, to expand their plants; secondly, to change over their processes to make foreign powder. These, together with the problem of securing a sufficient supply of raw materials, such as benzol, have been pretty well solved, and the production of explosives is proceeding on a tremendous scale. Many makers who have undertaken orders for shells have made heavy purchases of machine tools for

executing the orders; these firms have been unwilling to fill their existing plants with such special work at the expense of inconveniencing their regular customers. Evidently these firms are looking for a strong revival in domestic demands. The Westinghouse Electric and Manufacturing Company, after accepting a large order for rifles, bought two plants-the Stevens Arms Company and the Stevens-Duryea Automobile Company-in order to take care of the work outside of its Pittsburgh plants. Mr. J. F. Wallace, formerly chief engineer of the Panama Canal, thinks that, as

consequence of the huge orders placed, the United tates will have the means of providing for national efence; the plants now used for supplying European equirements could be used to equip home armies in remarkably short time. In other words, the United tates has obtained insurance against attack for pracically nothing, so far as equipment preparation will rovide.

IN the July issue of Man Mr. E. J. Wayland decribes a series of stone implements collected by him on the Monapo river in the Portuguese province of Mozambique, East Africa. All, with one possible exception, are extremely crude, being chipped out of nodules of chalcedony and jasper with which the basalt ridges of the sedimentary coast belt are bestrewn. There is no certainty about their age, the fact that they are found on the surface not necessarily showing that they are of comparatively modern date. They closely resemble those found by Mr. Lamplugh near the Victoria Falls. No local evidence justifies their attribution to a period earlier than the early Palæolithic, but they may be of much later date.

IN Man for July Dr. W. H. Rivers describes specimens of the boomerang found on the coast of Espiritu Santo, New Hebrides. They differ from the Australian type in having the ends almost square or showing a slight curve not continuous with the general curvature of the implement. The antiquity of the use of the boomerang in the New Hebrides may be assumed from its connection with tribal rites, and one group claim descent from it. This discovery raises an important problem. The weapon is generally regarded as an ancient element in Australian culture, but Dr. Rivers suggests that it was introduced by the race which, in his studies on Melanesian social life, he calls the Kava people. The discovery is, he thinks, sufficient to put us on our guard concerning the supposed antiquity of the Australian boomerang, for in spite of their difference of form, there can be no reasonable doubt that the Australian and Melanesian instruments are but divergent manifestations of the handiwork of one people."

IN his presidential address to the Royal Society of South Africa (May 19) Dr. L. Péringuey summarised the conclusions he has reached regarding Palæolithic man in South Africa. He still maintains that the early Palæolithic cultures-Chellean, Acheulean, and Mousterian-which occurred in sequence in Europe, existed together in South Africa. The later Palæolithic cultures, particularly the Aurignacean and Solutrean, are richly represented in South Africa, where they are associated, as in Europe, with a particularly realistic form of art. The evidence which associates the later Paleolithic cultures with the ancient Bushman is, in Dr. Péringuey's opinion, now quite complete. endeavours "to show that the Bushman, if himself not the ancestor of those Solutrean and Aurignacean people, may have been of them, and that he has retained many parts of their handicraft is equally certain." Dr. Péringuey is prepared to believe that the later Palæolithic cultures of Europe were introduced from South Africa.

THE Hydrachnidæ, or water-mites, are favourite subjects of study for students of "pond-life." Such students are indebted to Messrs. W. Williamson and C. D. Soar for an illustrated account of the genus Lebertia, which appears in the Journal of the Quekett Microscopical Club, vol. xii., No. 76.

A RECENT number of the Philippine Journal of Science (vol. ix., section D, No. 4) is almost filled by an exhaustive account of the Palæmons of the Philippines by Dr. R. P. Cowles; a feature of the paper is the careful series of measurements of the segments of the chelate thoracic limbs in the various examples of each species described.

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DR. A. RANDELL JACKSON, whose studies in British spiders are well known, has published (Proc. R. Phys. Soc., Edin., vol xix., No. 7) a Second Contribution to the Spider Fauna of Scotland." This includes a Clubiona, hitherto undescribed, and several species not before found in Great Britain. As might have been expected, Ben Nevis and the Cairngorm group of summits proved exceptionally good collecting grounds. But why does the author write "Ben McDhui," as if the famous Aberdeenshire mountain were named after a Highland clan, instead of preserving the original "Ben Muich Dhui" (=“Mount of the Black Hog")?

MANY marine animals of high interest have been made known through the activities of the Irish Fisheries Surveys. Some new light on the life-history of echinoderms has been shed by larvæ dredged or tow-netted off the south-west coast of Kerry, and described by Dr. J. F. Gemmill (Proc. R. Phys. Soc. Edin., vol. xix., No. 7). A single Brachiolaria larva, resembling that of Asterias rubens, is carefully figured; it was taken in a tow-net at 1150 fathoms' depth. An advanced bipinnaria stage, found in five different localities, and referred to Luidia ciliaris, is also described and drawn.

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ORNITHOLOGISTS may turn with profit to "Notes on the Moults and Sequences of Plumage in Some British Ducks," by Miss Annie C. Jackson, which appear in the July issue of British Birds, for there are yet some who hold that a colour change without a moult is not only possible but demonstrable, a conclusion based on an inability to weigh evidence and a want of knowledge of the structural peculiarities of feathers. But the merit of Miss Jackson's paper lies not so much in controverting these fallacious arguments as in establishing the fact that female surfacefeeding ducks undergo a complete moult in the spring. This moult extends also to the underclothing of downfeathers. But by far the most important item in her work is the discovery that at this spring moult an additional form of down, longer and coarser, is developed, apparently to serve as a lining for the nest. Presumably this peculiar type of down is developed on the breast alone. Further particulars of the structural peculiarities of this down, which disappears with the autumn moult, would be acceptable.

A VERY useful summary of what is known in regard to the emission of light among insects is given by Mr. K. G. Blair in the Proceedings of the South

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