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the Post-office tried to crush the box to the thickness of silver-paper. The bit contains no spicules, nothing but a mass of contorted tubes filled with small nuclei like ova. "The nuclei are about 1-600th of an inch in diameter, and I suppose they are in tubes. The part you sent was boiled in Liquor potassce; that is how the structure alone came out, but there were no spicules in it, examined in this way or in water alone, but many fat globules, and a few sheaf-shaped calcareous concretions, common in all preparations of animal matter."—September 5, 1873.

The habits of Pennatulida: are very imperfectly known and not at all understood. Dr. Johnston observes in the "British Zoophytes," voL i. p. 160, that the fishermen believe that the common Sea Pens, which they call Coxcombs, " are fixed to the bottom with their ends immersed in the mud." The Virgularia mirabilis are believed by the fishermen to have one end erect in the mud, and I'avonaria quadrangularis, according to Profesor Forbes, "lives erect, its lower extremity, as it were, rooted in the slimy mud at a depth of from twelve to fifteen fathoms." Mr. Darwin, who observed a species on the coast of Patagonia, which he called Virgularia pataqonica, says: "At low water hundreds of these zoophytes may be seen projecting like stubble, with the truncate end upwards a few inches above the surface of the muddy sand. When touched or pulled they suddenly drew themselves in with force so as nearly or quite to disappear. By this action the highly clastic axis must be bent at the lower extremity, where it is naturally slightly curved, and I imagine it is by this elasticity alone that the zoophyte is enabled to rise again through the mud."

Bohadsch, as quoted by Johnston, says that the Pennatulce swim by means of their pinner, which they use in the same manner that fishes do their fins. Ellis says : "It is an animal that swims freely about in the sea, many of them having a muscular motion as they swim along." And in another place he tells us, that " these motions are effected by means of the pinnules or feather-like fins, these are evidently designed by nature to move the animal backwards and forwards in the sea, consequently to do the office of fins." Mr. Clifton describes the Australian species as swimming rapidly in shallow water; and the American naturalists all seem to agree that the Stick Fish, Osteocclla seplentrionalis of liurrard Inlet, which has only a slight crest of polyps, and not pinner, or fins, as Ellis calls them, swims about like a fish, and is eaten by the dog-fish.

There seems to be no doubt that the Sea-Pens and SeaRushes do live in groups together, erect, and sunk in the mud, and that they arc sometimes found swimming free in the sea, but the question is, arc the free specimens those that have been disturbed by the waves and currents, and do they afterwards affix themselves in the mud, or are they vagrant specimens that live for a time and then die or are eaten by fish, their struggling being mistaken for swimming? Dr. Johnston observes, that when the SeaPens are placed in a basin or plate of water, he never observed a change of position, but they remain in the same place and lie with the same side up or down just as they have been put in. That is my own experience even when they are placed in a deeper vessel, but this may arise from the animal having lost part of its vitality before it was taken.

It may be useful to give the synonyma of these animals.

Osteocclla, Gray, Cat. Pennatulida;, 1870, p. 40. Ann. and Mag. Nat Hist. 1872, ix. p. 405.

Pavonaria, sp. Steams, Mining and Scientific Press. San Francisco, Aug. 9, 1873.

Verillia, Stearns, Californian Acad. Sci., Aug. 18, 1873.

1. Osteocclla cliftoni, Gray, Cat. Pennatulida?, 1870, p. 40; Ann. and Mag. Nat. Hist. 1872, ix. p. 406.

Hab., Western Australia (G. Clifton, Esq.), B.M.

2. Osteocclla seplenirionalis, Gray, Ann. and Mag. Nat. Hist. 1873, ix. p. 406 (style only).

"New Marine Animal," Sclater, Brit. Assoc, Aug. 20

1872; Nature, vol. vi. p. 436 (with figure of fish, a which it is said to be the notochord).

"Axis of Permatulid,"(H. N. Moseley, Nature. Sept 26, 1872, vol. vi. p. 432.

"Pennatulid," Dawson, NATURE, Oct. 24, 1873, vol. n. p. 516; Whiteaves, Nat. Hist. Soc. Montreal, 1872.

"New Aicyonoid," Steams, Proc. Cal. Acad. Sci., TA1873, v. part 1, p. 7.

Pavonariablakei, Stearns, MiningandScientific Prz San Francisco, Aug. 9, 1873.

Verrillia blakei, Stearns, Proc. Acad. Cal Acad. So. Aug. 18, 1873.

Hab., Gulf of Georgia, Barraud's Creek, near Ser Westminster, Washington Territory: Herd, Claudet. Doane, Steams, Chambers. Eraser's River: Dick and Nelson. B.M.

Mr. Stearns's paper in the Proceedings of the Californian Academy 01 Sciences is a reprint of the paper in the San Francisco Mining and Scientific Press, with a fr» additions, and the addition of a new sub-genus, Verrilht, although he quotes Osteocclla.

Since I have seen the proof of this paper, the Hon. Justice Crease has informed me that be has for warded to me a series of the animals of Osteocclla, and also an account of the animal from an examination of fresh examples by Dr. Moss; the latter has arrived, anJ I communicated it on September 25 to the Zoological Society; it is illustrated by figures. J. E. Gray

THE RELATION OF MAN TO THE ICESHEET IN THE NORTH OF ENGLAND

IN the interesting review of Sir Charles Lyell's ''Antiquity of Man," communicated to NATURE of Oci. 2, Mr. A. R. Wallace mentions the fact that "there is as yet no clear evidence that man lived in Europe before the Glacial Epoch, and even if he did so, the action of the ice-sheet would probably have obliterated all records of his existence." The fact was true when it appeared, but both the fact and the remark which follows it, may now have to undergo considerable modification. The Committee for the Exploration of the Victoria Cave, near Settle, Yorkshire, assisted by a grant from the British Association, have just made a discovery which may prove to be of the greatest importance not only to the geologists of Europe, but to all those who take an interest in the origin and early history of man.

In May 1872 the Committee were exploring a bunc bed in the cave, which occurred at a considerable depth beneath other deposits. It was full of hya?na-dung. broken bones, and teeth. A quantity of these were sent to Mr. Busk for determination, and he kindly returned the following list:—

Rhinoceros tichorinus

Bison

Ccrvus clap/tus

Elephas primigenius
Ursus spclicus
Ursus prisitis
Hyesna spelcca

These are well known to represent the fauna of the river gravels in the south of England. Among them was a bone which puzzled even Mr. Busk, and he has only now given his mature and definite opinion on the subject. He writes: "The bone is, I have now no doubt, human; a portion of an unusually clumsy fibula, and in that respect not unlike the same bone in the Menlone skeleton." When Mr. Busk has taken some time to consider the question there are few scientific men who will dispute his verdict. The occurrence of the bones of man villi this group of animals is a new fact for this part of the kingdom, but one that might be expected from a simil<ir co-existence in the south of England, in Kent's Cavern, Wookey Hole, and elsewhere.

But at Settle this discovery possesses a far greater interest from the evidence there of the relation of these animals and man to the great ice-sheet. This hyamabed dips into the cave, and has been worked only a short distance from its mouth ; but at the mouth itself, vertically under the farthest projection of the overhanging cliff, lies a bed of stiff glacial clay containing ice-scratched boulders. This bed dips outwards at an angle of about 400, and evidently lies on the edges of the beds containing man and the older mammals. It has been suggested that it may have fallen from the cliff above, and therefore may not necessarily have come into its position in glacial times, but, on a careful consideration, this is quite impossible. Upon it lies a great thickness of talus or scree, which is made up of fragments of limestone split off from the cliff above by the frosts of successive winters. If all this were now removed it would be barely possible for the glacial drift to fall from the cliff above to its present position, but if all the talus were restored to the cliff, of which it forms the waste, such a fall would be impossible. It is quite clear, from the waste of the cliffs which has taken place since the glacial drift came where it now lie?, that the cliff' then projected many feet farther out and would prevent such a fall.

A strong argument lies also in the fact that the loose talus all lies above the drift and is quite free from mud, whereas all the deposits below it arc heavily charged with it, and the mud is just such a fine impalpable stiff mud as would result from the grinding of gliders and the flow of glacier water. It seems probable that the drift is really the remnant of a moraine lateral orprofonde, left here by a glacier or an ice-sheet, and that the remains of the older mammals and of man disinterred from beneath it are of an age at any rate previous to the great ice-sheet of the Irish Sea basin. But there is another line of argument which tends to the same conclusion. Three years ago it was believed by most geologists that the fauna here disinterred had never existed in this particular area—and why? because their remains had never been found in any of the river deposits of the district. It was supposed that the great extension of the ice prevented their migration hither. It is clear, now that we have found these remains in caves, that they must have peopled the northern district at one time as thickly as they did the south of England, where their bones are so common in river gravel. But their remains in the northern district occur now only in caverns, and have been removed from the open country. When we compare this removal of the mammoth-fauna over certain districts with the presence of evidence of land glaciation on a great scale, we begin to see that they bear a definite relation to one another, and that the ice-sheet was the great " besom of destruction" which swept away all remains of the older inhabitants from those portions of the country adjacent to the great ice centres.*

Again, there is another matter relating to this question which has hardly received the attention which it deserves. This is the complete absence of palaeolithic implements and the fauna which is usually associated with them in the river gravels of the south,over co-extensive areas of the north of England, indicating the removal of palaeolithic man from those areas by the ice-sheet. If I am not much mistaken, this discovery at Settle may have an important bearing in several ways. It will carry back the proofs of the antiquity of man to a time previous to the ice sheet, that is to interglaciil if not to preglacial times. It will corroborate the opinions expressed by Mr. Godwin Austen, Mr. James Geikie, and others, that the older valley gravels of the south of England are not of an age subsequent to the Till of the North. And it will give some support to the views of Messrs. Searles Wood and Harmer, that the Till of the north- west of England, though older than the great submergence, is probably of younger date than the greater part of the drifts of the east coast.

* Qtologtittl Magatiiu, vol. x. p. lift.

The Cave Committee will continue their work with redoubled vigour. It is much to be hoped that the scientific public will come to their assistance, and not let the expense of the undertaking fall, as now, almost entirely on the district of Craven.t

R. H. TlDDEMAN

ATLANTIC FAUNA

LAST May the s.s. Hibernia belonging to the Telegraph Construction and Maintenance Company, was despatched to repair the French Atlantic Cable, in which a fault was indicated some 200 miles from Brest. A brief account of some of the animal forms obtained by me in that expedition may not be without interest to some of the readers of Nature.

To Mr. R. London, superintending the expedition, I am greatly indebted for the many facilities that he afforded me, of obtaining specimens of the deep-sea fauna. The first cast was made about 100 miles nearly due west of Brest, at a depth of 83 fathoms. Here we found numerous valves of Pecten, a fine Opliiocoma, with rays nine inches in length, which when handled broke itself into numerous fragments, Echinus lividus, Spatangus purpureus, &c.

At the surface we obtained by means of a towing-net a great abundance of a minute Entomostracous crustacean of a greenish-blue colour, with deep sapphire eyes, a Cydippc, two species of Idotaj and Polybius Hcnslowii.

On the Atlantic cable, which was raised to the surface at a point 112 miles west of Brest, were found numerous shells of a small boring mollusc, one of the Pholadidcc, apparently Xylophaga. The outer covering of the cable, consisting of tarred manilla hemp, was perforated in many places by the round holes which they had formed and in which their shells were found. In places they had penetrated the outer covering, and had passed between the iron wires to the gutta percha core, in which they had made numerous shallow indentations, but in no case had they penetrated this to any depth. This cable, it will be remembered, was laid in 1869.

We now steamed about 87 miles westward to the edge of the Little Sole Banks, where the water deepens from 90 to 480 fathoms within a distance of a few miles. Here the cable was again hooked and brought to the surface from a depth of about 300 fathoms. Adhering to its surface was a species of Pycnogonum in great abundance. The specimens lived for some time after being brought to the surface, and moved about sluggishly.

A few bright red anomourous crustaceans were also obtained. These were very active, and lived for some days in a bucket of water.

They had, while in confinement, a peculiar habit of drawing their claws over their head, antenna?, and eyes, which suggested the idea that they were confused and dazzled by the extraordinary amount of light to which they were exposed.

A species of Tiibularia of great beauty grew abundantly in clusters on the cable, and throve well in confinement. The cable was thickly overgrown with Scrtulanas of various species, moored to which by their hinder legs a species of" Caprclla, diabolic in appearance, but sluggish and inactive in nature, abounded.

A few miles farther westward the cable was raised from a depth of 480 fathoms. Sertitlarias, Tubu/arias, Caprclla, &c, were still abundant; but the Pycnogonum was conspicuous from its absence.

In the recent expedition in which the Great Eastern and Hibernia have been employed in endeavouring to repair the Atlantic Cable of 1S65, the natural history results have been much more meagre. Perhaps the most interesting objects obtained are some fragments of rock,

t Messrs. Birkbeck and Co., Craven Bank, Scale, have kindly consented Co receive subscriptions,

consisting of Hornblende with interspersed crystals of quartz, found in lat. 51* 56' N.,long. 35° 45' W., at a depth of about 1,760 fathoms.

Fred. P. Johnson

NOTES Prof. Sylvester has recently made a discovery which is likely to create some interest, not only amongst mathematicians, but also amongst mechanicians and instrument-makers. By means of a sort of lazy tongs he has succeeded in converting spherical motion into plane motion, a result, we believe, hitherto looked upon as unattainable. This discovery will form the subject of a communication which Mr. Sylvester is announced to lay before the London Mathematical Society at its Annual General Meeting on Thursday next (November 13).

The two gentlemen recently elected to Science-Fellowships at Oxford, are remarkable instances of success attending most irregular and unusual undergraduate careers. Mr. Yule was at one time a boy at Magdalen College School, he obtained the Rrackenbury Scholarship for Physical Science at Balliol College, but was obliged to throw it up after a short time, on account of his failure to pass the classical examinations of the University. He bethought him of the more merciful ordinances of the sister University, and having obtained a Scholarship at St. John's College, Cambridge, proceeded on his undergraduate course unchecked by the lessened barrier of the previous examination. After being placed senior in the Natural Sciences Tripos, he returns to Oxford, we may hope bringing treasures from the East—and at any rate ready to use his vote for the improvement of the Oxford Examination Statutes. Mr. Macdonald is an individual who has come as near as is possible to achieving the feat of being in two places at one time. In fact, theoretically, he has been in two places at one time. He had the great courage and energy whilst holding a position in the Education Office, to enter as an Undergraduate at Merton College, and by consent of the College authorities he kept his term by sleeping in Oxford, which place he left every morning during term, so as to be at his official post, returning in the evening in time for hall dinner. His office-holidays he employed in practical work in the Oxford laboratories, whilst analytical chemistry had to be studied in his own sitting-room, converted for the time into a workshop. Such a history makes it very certain that the examination system has not failed at Merton College to secure at any rate a most worthy recipient of the fellowship.

The election to the two vacant Fellowships at Merton College, took place on Oct. 30, when the choice of the electors fell upon Mr. John Wesley Russell, Lecturer of Balliol College, as Mathematical Fellow; and Mr. Archibald Simon Lang Macdonald Commoner of Merton College, as Natural Science Fellow. Mr. Russell was placed in the first class in Mathematics under Moderators, in Trinity Term, 1871 ; and Mr. Macdonild in the first class in Natural Science at the final examination, in Michaelmas Term, 1871.

We are glad to be able to add St. John's College, Cambridge, to the list of those which have opened their Fellowships to Students of Natural Science. Since 1S68, the College has given Exhibitions yearly, and Foundation Scholarships since 1870, for the encouragement of a knowledge of Physics, Chemistry, and Biology. On Monday last the Master and Seniors, in proof of their desire to place the Natural Sciences on the same fooling as Classics and Mathematics, elected one of their scholars, Mr. A. H. Garrod, B.A., who was a Senior in the Natural Science Tripos of 1871, to a Fellowship.

About the end of January 1S74, there will be an election to a scholarship in Natural Science at Exeter College, Oxford, can

didates for which will be examined in biology, chemistry, at: physics. Candidates arc not expected to exhibit tfitriaS ksasledge of more than one of the above subjects, and prefergj.will be given to a candidate who excels in biology, or one of c branches. The candidate selected will have to satisfy the =»lege that he has sufficient classical and mathematical knowiri; to pass responsions. There is no limit of age disqualifyirjj a^ didatcs for this scholarship. The scholarship is of the aacz. value of So/., tenable for five years from matriculation. Tb: scholar elected will have the use, during term, of a place ia ti histological laboratory of the college. For further informatx-t application should be made to Mr. E. Ray Lankester, Natsr^ Science Lecturer, Exeter College.

Mr. Charles J. F. Yule, of St. John's College, Cambridge wishes us to state that he is not "the Cambridge B. A ." whesr letter appeared in last week's number.

At the Commitia, held on Thursday, October 3a, ax tie Royal College of Physicians, Dr. Robert Druitt was elected 1 Fellow of the College. The president announced that tie Harveian Oration in the ensuing year would be delivered bjr Xt Charles West. The Gulstonian Lectures will be delivered b» Dr. J. F. Payne ; the Croonian Lectures by Dr. Murchison ; tie Lumleian by Dr. Sibson.

We regret to record the death, on Oct. 24, of Dr. dace Calvert, F.R.S., F.C.S. The illness which caused it was contracted at Vienna, whither he had gone to act as juror in the International Exhibition. The Journal cf the Society cj An: furnishes some particulars concerning the work of Dr. Calvert. As an analytical chemist his renown was European. He let England as a youth to pursue his education in France, and in the schools of that country secured many honours by the awardi which he obtained. He subsequently pursued the study of chemistry, and was appointed assistant chemist at the Gobelin works, under his learned master, Chevreul. Soon after his return to England, he commenced reading a series of papers before the Society of Arts on chemistry applied to industry. At a later date, when the Society of Arts proposed to establish Cantor lectures, he gave the proposition his hearty support, and delivered two courses of lectures on "Chemistry applied to the Arts." He also delivered courses on "Synthesis and the Production of Organic Substances," on "Aniline and Coal Tar Colours," and on "Dyes and Dye-stuffs other than Aniline." In 1846 he settled in Manchester, and was soos after appointed Professor of Chemistry at the Royal Institution there. He was also for some time a lecturer at the Manchester School of Medicine. His connection with the Manchester Sanitary Association led him to hygienic investigations—me of the principal results of which was a patent for the application and preparation of carbolic acid. In scientific circles great interest attached to Dr. Calvert's protoplasmic investigations, some of the results oi which were communicated in a paper read at the meeting of the British Association in Edinburgh some years ago, and afterward? published in the Transactions of the Royal Society. Dr. Calvert was a Fellow of the Royal Society of England, a Fellow of the Chemical Society, and an honorary Fellow of the Chemical Society of Paris. He was also a member of the Royal Academy of Turin, and of the Imperial Academy of St. Petersburg.

The death is announced of Prof. J. A. F. Breithaupt, of Freiberg, the well-known Mineralogist, on October 22, at the age of 82 years.

Ocean Highways announces the death from scurvy on the Novaya Zemlya Coast, of the distinguished Norwegian Arctic Explorer, Captain Sivert Tobieson.

At the meeting of the Royal Geographical Society lact Monday, Sir Bartle Frere, the President, said that, though there ■was no further news of Dr. Livingstone, the latest accounts of both the expeditions sent out in the hope of meeting him, tell of satisfactory progress. Of the West Coast Expedition under Lieutenant Grandy, R.N., the latest direct accounts state that the expedition had just left San Salvador, about June 16, in good health, so that we may one day hope to hear of their further progress in their search for tidings of Livingstone, and every step of their progress w 11 add to our knowledge of that mist interesting,but little known, region. Comparing Consul Newton's dates with those of Dr. Beke's Portuguese informant, published on Saturday last, Sir Bartle Frere thinks we must await some confirmation of the latter report before concluding that Lieutenant Grandy had turned back. The other expedition started under Lieutenant Cameron on the east coast, and notwithstanding all delays, Lieutenant Cameron made a fair start for the lake region ; and, by the latest accounts, was pushing on with every prospect of reaching a district where he was most likely to obtain tidings of Livingstone.—Mr. C. Markham, the Secretary, read a paper giving some interesting information connected with the voyage of the Polaris to the Arctic regions, and a discussion followed in which the desirability of another Arctic expedition was strongly urged, some of the members proposing that, if Government refused, the society itself should send one, but this view was controverted by Captain Sherard Osborne, who maintained that such an expedition, to be successful, should be under the auspices of the Government.

We have great pleasure 'in calling attention to a series of science lectures for clerks and working-men, which are to take place in South Place Institution, Finsbury. The first three lectures, on November 4, 11, and 18, are by Prof. Duncan, F.R.S., on the Geological History of the Earth, and these are to be followed by others on Light, &c. The gentlemen who get up these lectures deserve great credit, as they expect to be considerably out of pocket in their endeavour Jto place science lectures by the most eminent scientific men within the reach of the classes mentioned, who, we hope, will take ample advantage of the opportunity. The charge for admission is almost nominal.

Among the Local Societies, concerning which we have received information since we published our list, i» the "Junior Philosophical Society," a London Society which meets on the second and fourth Friday of each month from October to June, at 8 P.m. The Society seems earnestly bent on work in the way of reading papers, and occasional excursions, no member being admitted who does not prove his willingness to take his share in the work of the Society. Many of the papers to be read this winter are on important scientific questions; and we would recommend the Society to the attention of those young men who are within convenient distance of the meeting-place, 6a, Victoria Street, Westminster.

His Excellency Senor Don Gregorio Beintes, Minister Plenipotentiary of the Republic of Paraguay, has appointed Mr. Charles Twite, M.E., late reporter to the Royal Commission on Mines, who explored the mineral resources of Siam ; M. Balanza, botanist, late Commissioner of the French Government to New Caledonia and Egypt; and Mr. Keith Johnston, F.R.G.S., members of a scientific commission to inquire into and report on the natural resources of Paraguay. Dr. Leone Levi, F.S S., Professor of Commercial Law in King's College, Consul-General of Paraguay in London, will edit the reports and exhibit them in relation to the economic condition of the country. Such reports will be published towards the end of next year.

The Exhibition which will be held in Manchester, by the Society for the Promotion of Scientific Industry, of appliances for the Economical Consumption of Fuel, will be opened on December 18 next In connection with this subject, a gentle

man has placed a gold medal at the disposal of the Council of the Society for the best specimen of peat fuel that shall come nearest to coal in its use and character, special regard being had to its cheap and rapid production.

The Council of the Institution of Civil Engineers have forwarded us a list of thirty-six subjects, on which they invite communications.

Mr. Albert Muller has sent us No. 2 of his "Contributions to Entomological Bibliography up to 1862 ; " further numbers will appear as materials accumulate. The list contains a great deal of information, and it will no doubt be valued by entomologists. It may be obtained from Mr. E. W. Janson, Museum-street

The Director of the Imperial Russian Telegraph has given his consent to the transmission, free of cost, within the boundaries of the Russian empire, of messages announcing new astronomical discoveries.

Mr. James Dallas, of Benakandy, Cachar, writing us on the subject of inherited peculiarities, says that a friend of his has a black-and-tan English terrier dog, two inches of the end of whose tail is folded back so acutely as to come in contact with the upper portion. A pup, of which the dog is the undoubted father, has inherited the paternal peculiarity, with the difference that, instead of the end of the tail being turned up, it is turned down.

A Series of methodical observations on the various move ments of a ship affected by waves was carried^ out on board the ship Norfolk during her last voyage from Melbourne to London. The observations during the voyage (from July 24 until October 16) were effected by self-registering instruments, under the care of Mr. W. T. Deverell, on behalf of Mr. Spencer Deverell, of Portland, Victoria, who has devoted many years' study to the mathematical investigations of the movements of ocean waves and to their action upon a floating body. A complete report will constitute no doubt a valuable contribution to naval literature.

It is stated that the steamer Tuscarora, under the command of Capt. George E. Belknap, has lately been fitted up at San Francisco to undertake the labour of making soundings between the Pacific coast and Japan, in connection with the new cable route. On the detail of the Juniata, for service in the Polaris search, the sounding apparatus, which had been put on board for a similar sen-ice between New York and the West Indies, was transferred to the Tuscarora. This included a supply of new steel wire, with Sir William Thomson's patent reel. The vessel was to proceed early in July to Puget Sound, and thence, by way of the Aleutian Islands, to Hakodadi.

It is stated by the Australian and Atw Zealand Gazette, that the Government has signified its n illingness to grant a site for th proposed Adelaide university; to give 10,000/. towards the cost of its erection, provided an equal amount is raised by private subscription ; and to provide an annual grant equal to 5 per cent, on other subscriptions.

The great Exhibition of Vienna (we learn from the Journal of the Society of Arts') is to be commemorated by the establishment of an "Athenaeum," as it is called, modelled after the Conservatoire des Arts et Metiers of Paris, and the Museum of Industry at Brussels, for the special instruction of workmen and small manufacturers. It is to be installed in the midst of the industrial quarters of the capital. A large quantity of drawings, designs, models, instruments, machines, tools, raw and partially manufactured materials, have been promised by exhibitors, and Baron Schwarz-Senbom, director of the exhibition, has presented a collection of between three and four thous and volumes of book

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connected with industrial exhibitions. The establishment starts with a capital of more than 11,500/.

On Sept. 1, an earthquake took place at 4.10 P.M. with slight shocks at Drama, in European Turkey. There was an earthquake at about 9 P.M. on Sept. 6, in Armenia, at Er?eroum, and elsewhere. Several shocks of earthquake were felt on Aug. 21, in the City of Guatemela, but very few houses were damaged.

Ia Nature records the recent death of M. Godard, senior, the oldest of French aeronauts.

The additions to the Zoological Society's collection during the past week include a Bosnian's Potto (Perodicticus potto) from Africa, and a Blue Magpie (Cyano/o/iiis cyanus) from China, presented by Rev. A. W. Teter; two Ursine Dasyures (Dasyurus ursinm) from Australia, presented by the Acclimatisation Society of Victoria; an Alpine Marmot (Arctomys marmotta), an Inconvenient Curassow (Crax i/ieommoda) from S. America, a Red-bellied Thrush {Tun/us rufiventris), a Red Oven-bird (Furnariusru/us), and two Yellow Trupials (Xanthosomusftavus) from Buenos Ayres ; a Hoffmann's Sloth (Cholopus hoffmamii) from Panama, purchased ; a Sun Bittern (Eurypyga he/ias) from S. America, deposited.

THE SELECTION AND NOMENCLATURE OF DYNAMICAL AND ELECTRICAL UNITS*

rE consider that the most urgent portion of the task entrusted to us is that which concerns the selection and nomenclature of units of force and energy; and under this head we are prepared to offer a definite recommendation.

A more extensive and difficult part of our duty is the selection and nomenclature of electrical and magnetic units. Under this head we are prepared with a definite recommendation as regards selection, but with only an interim recommendation as regards nomenclature.

Up to the present time it has been necessary for every person who wishes to specify a magnitude in what is called "absolute" measure, to mention the three fundamental units of mass, length, and time, which he has chosen as the basis of his system. This necessity will be obviated, if one definite selection of three fundamental units be made once for all, and accepted by the general consent of scientific men. We are strongly of opinion that such a selection ought at once to be made, and to be so made that there will be no subsequent necessity for amending it.

We think that, in the selection of each kind of derived unit, all arbitrary multiplications and divisions by powers of ten, or other factors, must be rigorously avoided, and the whole system of fundamental units of force, work, electrostatic, and electromagnetic elements, must be fixed at one common level—that level, namely, which is determined by direct derivation from the three fundamental units once for all selected.

The carrying out of this resolution involves the adoption of some units which are excessively large or excessively small in comparison with the magnitudes which occur in practice ; but a remedy for this inconvenience is provided by a method of denoting decimal multiples and sub-multiples, which has already been extensively adopted, and which we desire to recommend for general use.

On the initial question of the particular units of mass, length, and time, to be recommended as the basis of the whole system, a protracted discussion has been carried on, the principal point discussed being the claims of the gramme, the metre and the second, as against the gramme, the centimetre, and the second; the former combination having an advantage as regards the simplicity of the name metre, while the latter combination has the advantage of making the unit of mass practically identical with the mass of unit volume of water ; in other words of making the value of the density of water practically equal to unity. We are now all but unanimous in regarding this latter element of simplicity as the more important of the two; and in support of this view we desire to quote the authority of Sir W. Thomson,

* First Report of the British Association Committee on Units.

who has for a long time insisted very strongly upon the ncccssiTr of employing units which conform to this condition.

We accordingly recommend the general adoption of the mrmetre, the gramme, and the second, as the three ranclarar v units ; and until such time as special names shall be appro pTii^ to the units of electrical and magnetic magnitude hence denvsd. we recommend that they be distinguished from "absolcce" units otherwise derived, by the letters "C. G. S." prefixed. these being the initial letters of the names of the three furuiatnexiiunits.

Special names, if short and suitable, would, in the opinion — most of us, be better than the provisional designations •* C O. -i

unit of "Several lists of names have already- L«-j_

suggested; and attentive consideration will be given to Jet further suggestions which we may receive from penens interest in'e'ectrical nomenclature.

The "ohm," as represented by the original standard coil, s approximately 10s C. G. S. units of resistance. Tbe ** volt ** a approximately 10* C. G. S. units of electromotive force, aai

the "farad" is approximately — of the C. G. S. unit ol

capacity.

For the expression of high decimal multiples and sub-multiple*. we recommend the system introduced by Mr. G J. Stoney—» system which has already been extensively employed for electrical purposes. It consists in denoting the exponent of tie power of 10 which serves as multiplier, by an appended cardirul number if the exponent be positive, and by a prefixed oriiEil number if the exponent be negative. Thus :—

10" grammes constitute a gramme-nine,

—5 of a gramme constitutes a ninth-gramme.

The earth's circumference is approximately four nietre-serexa, or four centimetre-nines.

For multiplication or division by a million, the prefixes mrga • and micro may conveniently be employed, according to the present cu-tom of electricians. Thus the megohm is a miHion ohms, and the microfarad \s the millionth part of a farad. The prefix mega is equivalent to the affix six. The prefix mi.r? a equivalent to the prefix sixth. The prefixes hlo, hcrt*, ,£zra, deci, centi, milli can also be employed in their usual senses before all new names of units.

As regards the name to be given to the C. G. S. unit of force, wc recommend that it be a derivative of the Greek Sum/ut. The form dynamy appears to be the most satisfactory to etymologists. Dynam is equally intelligible, but awkward in sound to English cars. The shorter form dyne, though not fashioned according to strict rules of etymology, will probably be generally preferred in this country. Bearing in mind that it is desirable to construct a system with a view to its becoming international, we think that the termination of the word should, for the present, be left an open question. But we earnestly request that, whichever form of the word be employed, its meaning be strictly limited to the unit of force of the C. G. S. system ; that is to say the force which, acting upon a gramme of matter for a second, generates a velocity of a centimetre per second.

The work done by this force, working through a centimetre, is the C. G. S. unit of work, and we propose to denote by it some derivative of the Greek Ipiov. The forms ergon, erga/, and erg have been suggested ; but the second of these has been used in a different sense by Clausius. In this case also we propose for the present to leave the termination unsettled ; and we request that the word ergon or erg be strictly limited to the C(j. S. unit of work, or what is, for purposes of measurement, equivalent to this, the C. G. S. unit of energy, energy being measured by the amount of work which it represents.

The C. G. S. unit of power is the power of doing work at the rate of one erg per second, and the power of an engine (under given conditions of working) can be specified in ergs per second.

For rough comparison with the vulgar (and variable) units based on terrestrial gravitation, the following statement will be useful :—

The weight of a gramme at any part of the earth's surface is about 980 dynes, or rather less than a kilodyne.

The weight of a kilogramme is rather less than a megadyne, being about 980,000 dynes.

Conversely, the dyne is about f02 times the weight of a milli.

* Before a vowel, either meg or megal (as euphony may sugglst), may employed instead of mega.

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