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not visited for a fortnight, they will return home, quickly, confidently, and by the shortest way.

These are four illustrative facts out of many, and the question is how they are to be interpreted. Some authorities still believe that there is no getting past the assumption of a non-analysable sense of direction, such as the Martian of Du Maurier's novel had of the North Pole. Others have swung to the opposite extreme of taking too simple a view, and maintain that it is altogether a question of scent: ants, like dogs, living in a smell-world. Others again lay too heavy a burden on muscle-memory, and others on visual impressions gathered by the way. Dr. Brun shows clearly, we think, that the power of way-finding is usually a composite product, and that there is no mysterious sense of direction.

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Of course, there are ants and ants, and there is no doubt that the scent of the nest, of the food, and of the pupæ sometimes counts for much. two adjacent sections of a pre-arranged ant-road be lifted and interchanged, the travellers go on just as they were doing; but if a section of the road-say a zinc plate-be lifted and replaced with its ends reversed, the ants seem to be perplexed at the boundaries, and there may be a temporary block. Facts of this sort have given rise to over-ingenious theories of polarised scent, of positive and negative scent, and so forth. This much seems clear, that the nest-smell gets fainter in proportion to the distance from home, and that the food-smell increases as the source of supply is approached; and it is very instructive to find that if an ant of one of the olfactory species be transported and placed in the middle of one of the ant-roads, it does not go home right away, but takes a tentative run first in the one direction and then in the other. In some genera, however, such as Formica, smell counts for little, and the obliteration of the scent by brushing the road or pegging down a spread-out newspaper does not disturb the homing. In connection with smell, it may be noted that the seat of the olfactory sense is in the tips of the mobile antennæ, where tactility is also located, so that tactile and olfactory impressions are closely combined.

To many ants the illumination is much more important than scent, as Lord Avebury proved long ago.

He got his ants to make a path across a wooden disc, concentric segments of which could be rotated, and found that if he turned a ring so that an ant on its journey was made to face the wrong way, it righted itself and proceeded in the old direction. But this was not the case when he made the experiment in uniform shade, or when he shifted the light at the same time as he rotated a segment of disc. One of Brun's experiments with a species of Lasius is very instructive. It was marching with the sun directly in its eyes, when the experimenter put an extinguisher over it, and kept it prisoner from 3 to 5 p.m. When it was set free at five o'clock, it turned its back on the position which the sun had reached, moving through 30°, and set off in a straight line homewards, eventually turning sharply to the left to

reach its original starting-point. Numerous experiments confirm the view that the direction of the light serves as a compass. When Santschi

shut off the sun with a large shade and made a false sun by means of a mirror, he got the ants, even on one of their main roads, to march in a direction either at right angles to the original one, or opposite to it, according to the position of the mirror. If, in the absence of sunlight, there be equal bipolar illumination of a given area, there is in many species no orientation.

From waxing and waning scent and from differential illumination, ants seem to build up associations, but this is not all. There is evidence in some cases of a memory of muscular movements, especially of the distance traversed, as if the ant kept its eye on a pedometer. There is something very interesting, too, in the phenomenon technically known as Turner's curves. A solitary ant that has travelled successfully from a considerable distance reaches a point quite near the nest; but instead of going on confidently, it stops as if perplexed. In many instances-80 per cent. in Cataglyphis bicolor-it proceeds to describe concentric curves, it may be for 5-15 minutes, and gradually draws near to the door of its home. Is it seeking for a sign, which might be a shining stone among the sand, or a scent, or the faint stridulation of one of its kin? Is it pursuing a trial and error method, very willing to be helped by any hint or combination of hints?

In some cases, e.g., Formica rufa, Brun has proved a baræsthesia, or feeling of gravity. A table was gently tilted, with the nest at the foot of the slope; a feast of honey was placed in the centre; the ants climbed straight up and straight down again. But if, while an ant was supping honey, the table was gently tilted in the opposite direction, so that the way to the nest was up-hill, the ant persisted in going down-hill as beforeaway from, not towards, home. Among the highest ants Brun finds distinct evidence of definite local memory, based on visual, topographical, and topochemical data, and lasting for two or three weeks at least. And only thus can we understand the confidence with which one of these creatures, transported to a distant part of its range, will make for home. There are ants which trust mostly to scent, and others which are largely guided by the direction of light, but for the higher ants the orientation is a complicated process, the outcome of the registration of manifold imprints received from the outer world-imprints relating to the quantity and quality of scents, the general direction of light, the illumination of particular objects, the slope of the ground, the feel of things, the distance travelled, the turns of the road, the direction of the wind, and even, perhaps, sounds. Individual ants hereditarily endowed with great sensitiveness, hereditarily attuned to receive certain kinds of tidings, serve an apprenticeship in the establishment of associations and reach a degree of perfection probably unsurpassed. Such is Dr. Brun's general position, which he defends

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with strong experimental evidence. There are still to be found old-fashioned fishermen who have attained within a certain range to a wonderful seamanship of an empirical sort; they have built up a body of associations from wind and from wave, from the sky and the "feel" of the sea, and they are seldom far out in finding their way home. And so it is with the higher ants, except that they work even more exclusively from an instinctive basis.

It must be remembered that the orientation power of ants does not stand magically alone. Even brainless animals adjust their body in a position of physiological equilibrium in relation to a stimulus of light or warmth or gravity--a static orientation. When there is direction of locomotion in relation to an external stimulus, we speak of dynamic orientation. This dynamic orientation may be direct or indirect. It is direct when the stimulus or goal is within the range of immediate senseperception, and it must be noted that for ants this range is only about a yard. Of this locomotor orientation there are various grades-tropistic, reflex, instinctive, and acquired, the first three expressing a hereditary predisposition, the fourth expressing the results of the individual's own learning. On a higher level is indirect orientation, where the goal is beyond the range of direct sensory perception. A complex of imprints or memories, corresponding to the goal, functions in the animal's sensorium, and forms the unifying centre of a whole series of imprints of the environment of the goal. What leads the creature on from step to step-often quickly and, so to speak, unquestioningly, if no contradictory interruption occurs is the recognition of localised stimuli corresponding to those of the unified reference series. The orientation implies a chain of recognitions, and the recognitions imply a registration of individual experiences. Without using Brun's somewhat forbidding mnemic terminology, we cannot do justice to his carefully worked-out theory, but we have indicated its general nature. It is essentially what may be called psychobiological, for he thinks of the organism as a historic being that trades with time, that enregisters imprints, and that has its past living in its present, as Bergson has accustomed us to say. These imprints, which the individual ant selectively accumulates, are not like sheets filed in a portfolio of reference; they are interpenetrated with and kept alive by their meaning for the actual everyday life.

PROF. JAMES GEIKIE, F.R.S.

BY Y the death of Prof. James Geikie, Edinburgh and its university have been deprived of one of the most prominent of its men of science, and geology has lost a distinguished investigator and successful teacher. The son of J. S. Geikie, of Edinburgh, whose literary talent found expression in a number of popular Scottish songs, the subject of this notice was educated at the high school and university of his native city, and in

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1861, when only twenty-two years of age, received an appointment upon the Geological Survey of Scotland, a service in which his elder brother, Archibald, had already been. engaged for five years. James Geikie's work as a surveyor lay chiefly in the south-west of Scotland, and in 1869 he was promoted to be a district surveyor; his studies seem to have been more particularly attracted, from a very early date, to the posttertiary deposits, and in various papers in the well scientific journals, as in the official memoirs of the survey, he published the results of his observations and his conclusions based upon them. Early in his career, James Geikie had become a great admirer and warm friend of Andrew Ramsay, then director of the English Geological Survey, and Ramsay's theoretical views and speculative suggestions found a stout supporter in the young Edinburgh geologist. In 1876 the Colonial Office requested Ramsay to proceed to Gibraltar in order to report on the important question of its water-supply, and James Geikie was chosen to accompany and assist him. In addition to the valuable report made to the Government, the two geologists were able to contribute to scientific journals memoirs dealing with. the geology of Gibraltar, and especially with the superficial and cavern-deposits, and their bearing on the history of the Mediterranean in post-tertiary times.

In 1874 James Geikie had already published his conclusions concerning the history of the Glacial period in Britain in his well-known work, "The Great Ice Age," which has passed through three editions; and in 1881, after devoting his vacations to travel on both sides of the Atlantic, he extended the bearings of his views on the subject by the publication of his "Prehistoric Europe."

In the following year, however, James Geikie entered upon a new field of labour. The appointment of his elder brother to the directorship of the Survey necessitated his vacation of the Murchison professorship of geology at Edinburgh, and James Geikie received the appointment, resigning his position on the Survey. During his energetic and successful work of teaching, carried on for more than thirty years, he published a number of very valuable educational books: "Outlines of Geology," of which four editions were called for; "Fragments of Earth Lore"; "Earth Sculpture," two editions; and "Structural and Field Geology," three editions. His labours were not by any means limited to the special subject of his studies; he was one of the founders of the Royal Scottish Geographical Society, acting as editor of its journal, and for a time as president of the society. He was also for many years dean of the faculty of science in Edinburgh University. In 1875 he was elected a fellow of the Royal Society, and in 1889 received the Murchison medal of the Geological Society, while he was a member and correspondent of many scientific societies at home and abroad.

It was not only in his numerous scientific writ

ings that James Geikie's hereditary literary instincts were exhibited, for he published in 1887 a series of translations from the German, "Songs and Lyrics by Heinrich Heine, etc." His frank manner and bonhomie won him many friends, and we may well believe that, though an ardent golfer, like so many other Scotchmen, he gave expression to the sentiment ascribed to him that he found a still more pleasant means of recreation in "loafing in pleasant places with a congenial friend." J. W. J.

BY

EMILE-HILAIRE AMAGAT.

Y the death of M. Emile-Hilaire Amagat at his country estate at Saint Satur in the department of Cher, France loses one of her most distinguished physicists. Born in 1840, he held several minor teaching appointments before becoming professor at the Ecole Normal at Cluny. Here in 1867 he commenced his researches into the behaviour of gases under high pressures, which rapidly brought him into the front rank as an experimentalist. At Lyons, where he had become professor at the Catholic university, he utilised the tower of one of the churches as the site for a mercury manometer giving pressures up to 80 atmospheres, and in one of the coal mines of Saint Etienne constructed one up to 430 atmospheres. His observations on nitrogen at these pressures enabled him to use the nitrogen manometer in his experiments on other gases, on liquids and solids, and on the conditions of transition from one state to the other. By the help of a skilled mechanic he had himself trained, he was able to construct apparatus for observations at pressures up to 3000 atmospheres. His results, which appeared for the most part in the Annales de Chimie et de Physique, were summarised in memoirs of dates 1883 and 1893, and his curves showing the variation of the value of pv as p increases for hydrogen, nitrogen, and carbonic acid have been reproduced in standard text-books for the last twenty years.

In 1892 Amagat was elected an honorary member of the Literary and Philosophical Society of Manchester, and in 1897 a foreign member of the Royal Society of London. After going to Paris as examiner for admission into the Ecole Polytechnique, he was in 1902 elected member of the Académie des Sciences. In 1906 he was president of the French Physical Society, and soon after was elected one of its few honorary members. Although offered a professorship at the Ecole Polytechnique, he preferred his examinership, and continued to devote to research much of the leisure it allowed him. During the last few years his health kept him at his country house, and for several months before his death he was confined to his room. For a generation he had been one to whom younger men could appeal for advice and encouragement in their work, and many distinguished physicists of to-day recall with affection his kindliness, his sincerity, and his modesty. C. H. L.

NOTES.

THE prospectus of British Dyes (Limited), which was put before the public a few days ago, has evoked universal condemnation in the daily Press. As might perhaps have been anticipated, the board of directors does not include a single representative of science, whilst the directors appointed by the Government consist of a railway director and a civil engineer. This characteristic neglect of science, and its consequences, form the subject of two letters by Sir William Ramsay and Sir Henry Roscoe, published in Wednesday's Times. Sir William Ramsay gives numerous instances to show that scientific chemists must form an important part of the directorate if the scheme is to be a success. The Castner Kellner process has on its board Sir Henry Roscoe and Dr. Beilby. The ammonia-soda process, originally patented by Dyer and Hemming, was successfully introduced and managed by the late Dr. Ludwig Mond. The paraffin industry was due to the late James Young, at one time an assistant of Prof. T. Graham. Perkin's and Spiller's names are associated with the early days of synthetic colours. These men were both pupils of Hofmann at the Royal College of Chemistry. The firm of Spencer, Chapman, and Messel, which has for many years manufactured sulphuric acid by the contact process, owes its inception and success to Dr. Messel. Turning to metallurgy, Lowthian Bell and Bessemer were scientific chemists first; successful manufacturers after. In short, it would be difficult to discover a successful chemical industry which has not been initiated and controlled by a chemist. Unless British Dyes (Limited)" copies this precedent, there is little hope for it.

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SIR HENRY Roscoe, in the letter referred to above, points out that it is not the manufacture of the wellknown colours of indigo, alizarin, or methyl blue which will bring financial and final success to British Dyes (Limited). The preparation of these articles-which, like all complicated chemical processes, requires both knowledge and great care-is on well-known lines. It is the new thing which makes a business success. "In the colour industry it is then the research chemist, and he alone, who can keep the flag flying, for he alone can bring forward new forces and create new developments. Capital cannot do it, business capacity cannot do it, but the brains, the imagination, the skill, and the knowledge of the research chemist can." Yet though this is the case, so far at least, the research chemist is to have no voice in the direction of affairs in the new colour company, but merely to be called in as an expert when, in the opinion of his business superiors, he can help them to solve some difficulty. If this plan is persisted in and the scientific chemist is not given a voice in the management "success is improbable, if not impossible.”

THE Bakerian lecture of the Royal Society will be delivered on Thursday next, March 18, by Prof. W. H. Bragg, upon the subject of "X-rays and Crystals."

WE regret to see the announcement that Principal Sir James Donaldson, Vice-Chancellor of the University of St. Andrews, died on Tuesday night, March 9, at eighty-three years of age.

THE death is announced, in his sixty-fifth year, of Prof. H. W. L. Tanner, F.R.S., formerly professor of mathematics and astronomy at University College, Cardiff.

Wɛ learn from the Morning Post that Jean Maspero, the son of Sir Gaston Maspero, the Egyptologist, was killed in the Argonne on February 18 while leading his section into action.

PROF. SAMUEL W. SHATTUCK, for forty-four years professor and comptroller of the University of Illinois, died at his home in Champaign on February 13. Since 1868, says Science, Prof. Shattuck served the University of Illinois. For thirty-seven years he was head of the department of mathematics and from 1873 to 1912 he looked after the business affairs of the University.

ON Tuesday next, March 16, Sir J. G. Frazer will begin a course of two lectures at the Royal Institution on the belief in immortality among the Polynesians; and on Thursday, March 18, Dr. Aubrey Strahan will commence a course of two lectures on London geology. The Friday evening discourse on March 19 will be delivered by Prof. G. H. Bryan, on the modern pianoplayer-scientific aspects, and on March 26 by Sir J. J. Thomson on experiments in slow kathode rays.

WE regret to announce the death on March 6, in his eighty-seventh year, of Lieut.-General J. F. Tennant, F.R.S., past-president of the Royal Astronomical Society. When a young man, Lieut.-General Tennant was assistant to the Trigonometrical Survey of India. He served as Government Astronomer of Madras in 1859, and was afterwards transferred to the Public Works Department as an executive engineer, first, in Burma, then in the Punjab, and later in Bengal. He made observations of the solar eclipses of 1867-68 and 1871, and was in charge of those of the transit of Venus at Rurki and Lahore in 1876.

THE death is announced of Mr. Flaxman C. J. Spurrell, aged seventy-two. For many years he was interested in the geology of the Thames valley and co-operated with his father, the late Dr. Flaxman Spurrell, in collecting Pleistocene mammalia from the river-deposits at Crayford, Kent. In 1880 he described to the Geological Society his discovery at Crayford of a Palæolithic land-surface showing evidence of flint-implements in process of manufacture. The whole of the collection, both of mammalian remains and of flints, was presented to the British Museum (Natural History) in 1893 and 1895.

THE death is announced, at fifty-eight years of age, of Mr. William Willett, the promoter of the Daylight Saving Bill. The Bill proposed that clocks and other timepieces in Great Britain and Ireland should be put on an hour on the third Sunday in April of every year and put back again on the third Sunday in September. Mr. Willett was able to obtain support for this measure from many city corporations and town and district councils, in spite of the serious objections to it, but though the Bill was introduced into the House of Commons on two separate occasions it never reached the final stages. Mr. Willett was a fellow of the Royal Astronomical Society.

THE Council of the British Association, in consultation with the local executive committee at Manchester, has decided that the annual meeting of the association: shall be held in that city as arranged, in September next. Both the committee and the council have felt that it would be inexpedient under present conditions to offer an elaborate local hospitality in the form of social and other arrangements, which has been extended to the association on former occasions. The committee, however, expressed its desire that the long continuity of the yearly meetings should not be broken, and stated that it would "prefer that the meeting should be held although restricted to its more purely scientific functions."

THE War Office has just published the following table showing the distribution of the cases of typhoid which have occurred in the British Forces in the Field, between the categories of uninoculated, the fully inoculated, and the partially protected :

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LORD KITCHENER, Secretary of State for War; Dr. A. Strahan, F.R.S., director of the Geological Survey of Great Britain; and Prof. P. Vinogradoff, Corpus professor of jurisprudence at Oxford, have been elected members of the Athenæum Club under the provisions of the rule which empowers the annual election by the committee of three persons "of distinguished eminence in science, literature, the arts, or for public services."

WE learn that no fewer than thirty-seven members of the established staff of the Natural History Museum are at present serving with the naval or military forces, about half of them having joined their units at the front. Among these are Capt. E. E. Austen, who has for many years had charge of the Diptera in the museum; Lieut. C. Court Treatt, assistant in the bird-room, Mr. A. K. Totton, who was recently appointed to the invertebrate section of the department of zoology; Mr. H. F. Wernham, assistant in the department of botany; and Mr. W. N. Edwards, the newly appointed assistant for the study of fossil plants. In addition to the members of the established staff ten temporary assistants and fortyseven sons of the former class have joined the colours, while the museum has also furnished an efficient Red Cross Section and a platoon for the Volunteer Training Corps for Home Defence.

SOME few years ago the buildings of the Aquarium at Rothesay, which was for a time one of the wellknown "sights" of the Clyde, were taken over by the Marquis of Bute. The buildings have, through the generosity of the Marquis, provided a local habitation for the Buteshire Natural History Society, of which Dr. J. N. Marshall is president, while they have also served to house a valuable and developing museum collection illustrative of the local fauna and flora. Lord Bute has now installed a small laboratory for biological research and provided the most

necessary equipment, including a motor-boat. Mr. L. P. W. Renouf, of Trinity College, Cambridge, has been placed in charge, and as he is desirous of making the laboratory a thoroughly convenient centre for research work upon the wonderfully rich marine fauna and flora of the Clyde estuary, he will be grateful for the gift of books and pamphlets bearing upon marine zoology and botany. Any such gifts should be forwarded to the Bute Museum, Rothesay, N.B.

THE death is announced, in his seventieth year, of Dr. C. E. Bessey, professor of botany since 1884 at the University of Nebraska. For fourteen years previously he had held a similar post at the Iowa Agricultural College. From 1880 to 1897 he was botanical editor of the American Naturalist, and since 1897 he had been botanical editor of Science. Prof. Bessey had at various times occupied the presidential chair of the American Association for the Advancement of Science, of the Botanical Society of America, of the Society for the Promotion of Agricultural Science, of the American Microscopical Society, and of the natural science department of the National Education Association. He was the author of The Phylogeny and Taxonomy of Angiosperms," "Plant Migration Studies," and "Outlines of Plant Phyla," as well as of several botanical text-books for schools.

WE referred in NATURE of February 4 (p. 622) to reports from a number of correspondents that the battle in the North Sea on January 24 was accompanied by much disturbance among pheasants in Lincolnshire, Yorkshire, and even in Cumberland. The disturbance was most noticeable between 9.45 and 10.30 a.m., that is, as we know from Sir David Beattie's report, at the time when the Blücher received its principal injuries before sinking. In woods near Burgh-le-Marsh in Lincolnshire, the guns were heard simultaneously with the crowing of the pheasants. Canon Rawnsley, who has collected many reports on the subject, infers that "the pheasant's ear is capable of receiving impressions from soundwaves that the human ear cannot respond to” (Times, February 22); but, in a later issue (March 6), Dr. Davison suggests that the disturbance might be caused by the sudden swaying of low trees and undergrowth during the passages of the air-waves. directs attention to the fact (see NATURE, vol. xii., pp. 377-9) that, during a naval review at Cherbourg on July 18, 1900, the reports were heard for 107 miles, while windows for another thirty miles were shaken by the inaudible air-waves.

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ON Tuesday evening, March 9, Mr. George E. Brown, the editor of the British Journal of Photography, at a meeting of the Royal Photographic Society, described a method of colour photography that has recently been worked out at the Eastman Kodak Company's research laboratory at Rochester, N.Y. It is a two-colour method, and as blue is suppressed or represented in only a modified way, the process is not claimed to be suitable for other work than portraiture. The many fine examples shown prove that it gives excellent results, and that the lighter tones, such as those of flesh tints, white kid gloves, pearls, and so on, are particularly well rendered. The darker

colours, such as the browns, are very rich, but in the absence of the original materials photographed, it is not possible to say how nearly the colours are imitated. The process consists in taking two negatives, one through a red and one through a green screen, developing and fixing them, then dissolving away the silver image, and staining the films, the red record green, and the green record red. The dyed plates are placed face to face (one is taken reversed to permit of this) and constitute the portrait. It has to be viewed as a transparency, those shown being adjusted in colour for incandescent electric lamps behind a diffusing ground-glass screen or its equivalent. If preferred, the original negatives may be kept as such, and ordinary positives prepared from them. These positives may then be made to furnish any number of negatives for conversion into colour portraits. We learn that the process has already been taken up enthusiastically by American portrait photographers.

THE most interesting contribution to vol. vii., part 4, of the Journal of the Gypsy Lore Society is the first part of an account translated from the Arabic of Father Anastas, the Carmelite, describing the Nawar or Gypsies of the East. The description of them is the reverse of complimentary: "swindling rogues, lewd adventurers, wicked nomads, heedless ruffians," preserving a language of their own but destitute of any religion-the last statement interesting if it be correct. They are believed to be a mixture of Indians, Persians, Kurds, Turks, and Tartars, with the offscourings of the regions in which they have lived. Their name, Nawar, is, it is suggested a corruption of Lur, the Persian wanderers who are noted for theit skill in thieving, sleight-of-hand, and powers of witchcraft, and they may possibly be ultimately traced to the Indian peninsula. The author writes from personal knowledge of them, and he gives full references to the literature of the subject.

ACCORDING to the Museum Journal for September. 1914, a fine piece of art metal-work from the celebrated Dictæan Cave in Crete has found its way to the Philadelphia Museum, It is a unique bronze blade with incised designs, to which the nearest parallel is supplied by the inlaid daggers from the shaft graves at Mycenæ, but these are more elaborate in design and more beautiful in technique. The blade is 6 in. in length and is covered with a fine green patina. It probably belongs to the Late Minoan III. period. On one side a hunter is attacking a mighty boar with a spear, the jungle being indicated by a tuft of fern-like sprays between the sportsman and his victim. On the other side is represented the critical moment of an exciting bull fight, one bull clearly getting the worst of the encounter. Similar fern-like sprays on the quarters of one animal possibly represent the furry lines of his coat where the direction of the hair changes. The museum has also acquired a fine series of reproductions of the gems of Minoan and Mycenæan art-several swords and daggers, gold and silver cups from Mycena and Vaphio, faïence objects from the shrine of the serpent goddess at Knossos, and reproductions of some of the frescoes, including the famous cup-bearer.

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