official visit the other day to the schools of apprenticeship esta. blished at the expense of the City of Paris in the rue Herold and the boulevard of La Villette. The time required for the scientific education of the young workmen is three years. During the first year the pupils are trained in working wood as well as iron. The choice of the speciality is only made at the beginning of the second year. No work is executed without a drawing having been made, so that the workman is enabled to understand the use of the object he is manufacturing. Regular courses of lectures are given in the establishment on scientific subjects. Meanwhile experiments are conducted in three different

LIB32AR

340 metres, by help of the boring machines, and in spite of the

hardness of the rock the daily progress is two metres. The SITY ·

upper shaft is some 100 metres behind.

A NUMBER of Roman antiquities were found last year during some military earthwork operations near Metz, close to the Lunette d'Arçon. It appears that the place was one of the most important burial-places of Roman Metz. The Metz Geological and Archaeological Society gave the details at its last December meeting. Some thirty-five vases, four metal objects, three coins, and two tombstones with inscriptions are mentioned. Of human remains four skulls were found, one of which was

PROF. HULL has published a fourth edition of his "CoalFields of Great Britain" (Stanford). This edition has been largely rewritten, and contains an entirely new chapter on Carboniferous Plants, by Prof. Williamson, F.R.S. The Classifi cation of the Carboniferous Series of Beds has been modified in accordance with the views enunciated in Prof. Hull's paper on this subject read before the Geological Society in 1877. Various other modifications have been made in accordance with the results of recent geological research, and the statistical portions have been brought down to 1878.

MESSRS. LONGMANS AND CO. send us the fourth edition of Prof. Atkinson's "Natural Philosophy for General Readers and Young Persons," translated and edited from Ganot's French work. To this edition have been added twenty-five pages of new matter and sixteen additional illustrations.

MR. E. S. BAKER, photographer of Bristol, sends us a photograph of a jar, which is a fine illustration of the fact that water expands on freezing. During the recent frost the water in the jar froze, and the ice is seen protruding from its mouth to a considerable distance like a well-shaped cork.

MR. C. V. RILEY of 1700, Thirteenth Street, Washington, writes to us that, having been obliged to cease the publication of the American Entomologist, he has a few full sets of vol. iii., just closed, to dispose of, and has concluded to send the full volume to all former subscribers who may want it, or to any Library, Natural History Association, or editor of journal, postage prepaid, at the reduced price of $1.50. The information in the magazine, Mr. Riley states, is of permanent interest, and the volume will be of value to any one interested in entomology in any of its bearings.

M. CH. JOLY has republished as a pamphlet a paper which he lately contributed to the Journal of the National Horticultural Society of France, under the title of "Note sur une Exposition de Géographie botanique et horticole, organisée par la Société Centrale d'Horticulture de Nancy."

NEW SOUTH WALES, Victoria, and South Australia have agreed to jointly bear the expense of exterminating the Phylloxera vastatrix, the alarming extension of which in Victoria has threatened the destruction of the wine industry.

We have received the three first numbers for this year of the Chicago Field, which seems modelled on a small scale after its well-known English contemporary.

THE Revue Scientifique of January 29 contains a lecture recently given at the Sorbonne by M. Faye, on the Volcanoes of the Moon.

AT Cracow a new Polish review for literature, science, and art is now being published fortnightly. Its title is Museum, and its editor Dr. Thaddaeus Rutowski.

THE works in the Arlberg tunnel are progressing. On the Tyrolese side the lower shaft has been pushed to a distance of

bone remains in a round stone urn. The inscriptions were epitaphs; of the three coins, one dated from the year 41 (when Claudius commenced to reign), another from the year 160 (reign of Antoninus Pius). Prof. Schaaffhausen of Bonn states that three of the skulls found belong to three different tribes. One belonged to a German, another to a Frisian, the owner of the third came from so far a country as Lapland.

A REMARKABLE discovery of Russo-byzantine antiquities was made near Kiew some weeks ago, when a canal for the waterworks of the city was being excavated. They consist principally of twenty gold and enamelled lockets, three buttons of the same materials with heads of saints upon them, gold rings, agraffes and studs, all dating from the fifteenth or sixteenth century; they doubtless served as ornaments upon the costumes of the grand princes. Besides these some thirty-four silver coins were found, also a highly original bronze vessel in the shape of a fabulous quadruped. The metal value of all the antiquities is estimated at Icoo roubles (150%.). The Archæological Commission has taken possession of them.

OUR ASTRONOMICAL COLUMN

THE OBSERVATORY OF HARVARD COLLEGE, U.S.-We have received the Annual Report presented to the Visiting Committee of this Observatory by Prof. Pickering on December 6. The year has been one of unusual activity in the establishment, having enabled both the equatorial and meridian circle to be funds which had been liberally forthcoming from its friends regularly employed, and further having allowed of many researches of importance being conducted with the smaller instruments. With the large equatorial Prof. Pickering claims observations for position of the satellites of Mars at the last that he has succeeded in making a more extensive series of opposition than was obtained elsewhere, and states that Deimos was last seen at Harvard Observatory; the number of observed angles of position of Deimos was 825, and of Phobos 278, and that of observed distances 245. In addition to measures for position photometric observations were made, which appear to show that if the satellites possess a capacity for reflecting sunlight equal to that of the planet, Deimos may have a diameter of about six and Phobos of seven miles. It was noted at various observatories that Deimos appeared somewhat brighter in 1879 than at the preceding opposition in 1877, and in both years Prof. Pickering states it seems to have been brighter measured photometrically, and to have been seen more easily when it followed than when it preceded Mars.

Photometrical determinations of the times of eclipses of Jupiter's satellites, commenced in the summer of 1878, have been continued during the year, and it is considered with reasonable hope that these phenomena may be more accurately observed than hitherto by this method. Observations of planetary nebulæ described in the previous Report have been nearly completed.

With regard to spectroscopic observations, Prof. Pickering says the most remarkable discovery is that the spectrum of No. 17681 of Oeltzen's Catalogue, the place of which for 1880 is in R.A. 18h. Im. 17s., N. P.D. 111° 1', possesses a peculiar character. "The light of this star is principally concentrated in yellow, a little more refrangible than the D line. two points of the spectrum, one in the blue, the other in the A faint continuous spectrum is also seen."

The variable star of Ceraski, the true period of which was determined at Harvard College, is referred to; systematic observations have been made upon it. The Report describes the progress made in observations with the "meridian photometer,' whereby it is intended to determine the light of all stars visible to the naked eye between the North Pole and N.P.D. 120°. The principal want of the Observatory at the present time is stated to be the means of publication of these and other classes of observations, the large number of volumes issued during the last five years having exhausted the funds specially appropriated for defraying expenses of publication.

CERASKI'S VARIABLE STAR T CEPHEI. · Prof. Julius Schmidt, from his own observations of minima of this variable in the last five months of the past year, finds reason to conclude that in that interval each successive period was longer by o'08753m. or 5'25s. than the preceding one, and has calculated the times of minima upon this assumption between June 11, 1880, and February 15, 1881. For elements with this correction to the period to be applied, be adopts for his startingpoint

...

Minimum 1880, December 7, 10h. 6'7m.
Athens M.T. + 2d. 11h. 50'812m. E.

E being the number of periods from December 7. Thus the next minimum is found to occur on February 5, at 6h. 50*3m. Athens time, or at 5h. 15'4m. M.T. at Greenwich. Prof. Schmidt has remarked what we believe was soon detected by Mr. Knott from his observations in October last, that for more than two hours about the minimum there is no perceptible variation of brightness; decrease and increase are very rapid, particularly the latter.

SWIFT'S COMET, 1880 e.-The Superintendent of the Obser vatory at Washington, Admiral Rodgers, communicates to Science of January 10, an orbit of this comet which has been calculated by Prof. Frisby from three meridian observations made there on October 25 and November 7 and 25, and without any assumption as to the periodic time. The revolution resulting from this application of the general method is about 2178 days, or a little less than six years, and thus the conclusion arrived at by MM. Schulhof and Bossert of Paris, and Mr. S. C. Chandler of Boston, U.S., receives confirmation. From the position of the orbit it happens at present that only every second return to perihelion can be made available for observations.

BARON DEMBOWSKI.-Practical astronomy has sustained a severe loss in the death of Baron Ercole Dembowski, which took place on the evening of the 19th ult. at Monte, Frazione di Solbiate, Arno. Few have attained as great skill or exhibited greater industry and patience in that somewhat difficult and tedious branch, the measurement of the double stars, to which the Baron specially devoted himself, and we hope some means may be found of publishing in a collective form the results of his long-continued labours in this direction.

METEOROLOGICAL NOTES

OUR readers will learn with much satisfaction that Sweden has resolved to take part in the international meteorological and magnetical observations in the Polar regions, and arrangements have been made for carrying on the observations from June 1, 1882, till June 1, 1883. The house erected at Masselbay in Spitzbergen by Nordenskjöld's expedition, is still in good condition, and will be fitted up for the observatory. In connection with the Spitzbergen Observatory, Haparanda, at the head of the Gulf of Boothnia, is to be created into a first-class observatory, and furnished with Theorell's self-registering and printing meteorological apparatus; and all other observations will be made which are expected of a first-class observatory. M. Hjeltström is appointed director of the Haparanda Observatory. The funds to meet the expenses of the expedition and the two observatories have been most generously supplied by M. L. O. Smith, Stockholm. Prof. Hildebrandsson, the eminent Swedish meteorologist, has been entrusted with the discussion of the observations made by Prof. Nordenskjöld on the celebrated Vega Expedition, to the publication of which meteorologists will look forward with the liveliest interest.

IN his fourteenth contribution to meteorology Prof. Loomis returns to the discussion of the interesting question of the course and velocity of storm centres in tropical regions. In a previous communication he had shown that in middle latitudes the average

progress of storm centres corresponds pretty closely with the average direction of the prevailing wind of these latitudes. In marked contradistinction to this result is that now obtained regarding the course of the intertropical cyclones which occur within the region of the North-east Trade Winds. These cyclones, instead of following the ordinary course of the Trades towards the south-west, advance westward, but in a direction somewhat north of west.

DURING the winter months, storms while crossing the United States frequently advance during a part of their course from north-west to south-east. This course is followed most frequently in the region between the Rocky Mountains and the Mississippi, is seldom continued as far south as lat. 30°, and the storm centre, after reaching its most southerly point, often changes its course towards the north-east. Storms which cross the United States north of lat. 38° generally pursue a course a little to the north of east; while those which come from south of that latitude pursue a course nearly north-east. During the summer months however few storms travel south of lat. 38°, and during this part of the year the average course of storms is almost exactly towards the east.

PROF. LOOMIS next institutes a comparison between the West India hurricanes and those of the Bay of Bengal, China Sea, &c. The average course of the latter is towards the west, ranging from 13° south of west to 86° north of west, which agrees closely in this respect with the general course pursued by West India hurricanes. The velocity of their onward course is however markedly different, being only about eight miles per hour, which is less than half the average velocity of the West India cyclones. The average latitude when the course becomes north is nearly lat. 20°, being 10° more to southward than in the West Indies, and the velocity during this part of the course is only about nine miles an hour. Ultimately the cyclones curve round and pursue a course nearly east-north-east, with a velocity of onward movement scarcely reaching ten miles an hour, or le s than half of the velocity found for West India hurricanes. Lastly, while in the West Indies cyclones or hurricanes have been found no farther south than lat. 10° N., in Southern Asia they have occurred as far south as lat. 6° N.

THE concluding part of the Contribution is taken up with an examination of those storms of middle latitudes which advance in a westerly direction. In these cases, which may be regarded as abnormal directions, it is found that the wind is generally While greatest on the east side of the low centre of the storm. there are thus on the east side of the low pressure areas, causes tending to increase pressure on that side, there are different conditions on the west side tending to divert the winds westward, and this, Prof. Loomis thinks, is the most important reason why in such cases the storm centres advance to westward. In the United States, over the Atlantic, and in Europe, the influence of one area of low pressure upon another is a very common cause of abnormal movements of storm centres-such, for instance, as the coalescence of two low areas into one, resulting occasionally in an apparent westerly movement of the centre of lowest

pressure.

THE "Results of Meteorological Observations made_at Mauritius during 1877" fully sustains the high reputation of Dr. Meldrum's previous reports for fulness of detail, accuracy, and special observations not usually given in meteorological reports. readings of the barograph for the year, and a valuable table is The hourly monthly values have been calculated from the appended to this part of the report (p 5), showing the mean monthly diurnal variation of atmospheric pressure for the three years 1875-77. The value of these results will be greatly enhanced when the thermograph which has been received has been got into working order. A comparison, a very satisfactory one, is made of the barograph readings with those of the standard barometer. As in 1876 the wind during 1877 attained its annual maximum velocity in the colder months from June to August, and its minimum in the warmer months, from November to March; and its diurnal maximum velocity from II a.m to 2 p.m., and its minimum from about 2 to 5 a.m. The departures, however, from these times are such as to point to a considerable number of years' observations as required before the true average can be ascertained. Thirty-one stations for recording the rainfall are now in working order, and in each case the annual amounts available from 1862 are printed, and the averages of the years given for each station. Mean temperatures for seven stations appear in the repot, the three highest

stations, with the mean temperatures for 1877. being, Curepipe (1800 feet) 68° 3, Bonne Veine (1500 feet) 69°5, and Midlands (1400 feet) 73°2. The difference in height (400 feet) of the first and last of these, and the difference of their mean annual temperatures, 4°9, call for inquiry, and in connection therewith it may be suggested that a small map showing the physical features of Mauritius and the positions of the various stations would usefully illustrate these reports. As regards thunderstorms, which are carefully recorded, none occurred from May to October during 1876 and 1877, and the daily maximum is from I to 4 p.m., with a tendency to a secondary maximum about sunset, and the daily minimum from 10 p.m. to a little after sunrise.

IN a supplement to No. 366 of the Bulletin International of the Paris Observatory M. Mascart gives an interesting and rapid sketch of the meteorology of Europe for December last, illustrated with two maps showing the storm-tracks over the Continent during the month. During the first half of the month the storm-tracks were all to northward of the British Isles and Denmark, and fine weather prevailed particularly in Scotland, Denmark, and Germany. In France high barometers ruled with light winds, and temperatures high for the season. The contrast afforded with the weather in France during December, 1879, is is most striking; thus on December 10 of both years barometers were unusually high in France, but in 1880 the mean temperature was 50° 5, whereas on December 10, 1879, the mean temperature was -14°1. The bearings of the geographical positions of anticyclones, with their high pressures, on the temperature of the regions covered by them is a point well worthy of examination. The influence of a high-pressure area resting over the Atlantic and extending on its eastern side over Western Europe, has doubtless a very different influence on the temperature of that part of the Continent than an area of high pressure covering the Continent and terminated on its west side by France and Spain, even though the barometer be equally high over the west of Europe. During the second half of December the storm-tracks took a much more southerly course, several being as far south as the Channel and the north shores of Germany. The result was an extension south of the cold, so that in Orkney and the Hebrides temperatures were nearly 30 below the normal, on the Tweed about the normal, rising farther south to 1°1 above the normal in North Wales, 5°o in the Channel Isles, and 67 in Paris. During December, 1879, temperature in Paris was 21°2 below the normal, the mean for that month being 17°6, or 27°9 colder than that of last December.

GEOGRAPHICAL NOTES

ON Tuesday night, at the Royal Institution, Mr. Edward Wymper described his ascents of Chimborazo and Cotopaxi to a distinguished audience. While purely athletic mountaineers had his sympathy in the practice of mountaineering as a sport, Mr. Whymper confessed that his sympathies were much more with those who en ployed their brains as well as their muscles. His journey to the Andes was to be one of work, and all its arrangements were devised so as to economise time to the uttermost. In observations for altitudes and position, in studying the manners and customs of the country, in photography and sketching, in the collection of objects of interest, from beeties on the summits of mountains to antiquities buried in the ground, he found quite sufficient to occupy his time. From Bodegas the party was composed of two Swiss mountaineers, the cousins Carrel of Val Tournanche, Mr. Perring, some muleteers, and their teams. When they reached the summit of Chimborazo, on the 3rd of January, after a most arduous climb, they found the wind blowing at the rate of 50 miles an hour, from the north-east, and driving the snow before it. With extreme difficulty, a reading of the mercurial barometer was effected. The mercury fell to 141 inches with a temperature of 21 deg. Fahr. This being worked out, in comparison with a nearly simultaneous observation at Guayaquil, gave 20,545 feet for the height of Chimborazo. They began the descent at 20 minutes past 5, with scarcely an hour and a quarter of daylight, and reached their camp (about 17,400 feet above the sea-level) about 9 p.m., having been out nearly sixteen hours, and on foot the whole time. Passing from an extinct to an active volcano, Mr. Wymper next gave an account of his journey to the crater of Cotopaxi. Observing with the telescope, during an enforced stay

at Machachi, that much less smoke or vapour was given off at night than by day, he resolved, if possible, to pass a night on the summit. On the 18th of February the party got to the edge of the crater, having passed almost the whole way from their camp at a height of 15,000 feet to the foot of the final cone over snow, and then over ash mixed with ice. The final cone was the steepest part of the ascent, and on their side presented an angle of 36 deg. When they reached the crater vast quantities of smoke and vapour were boiling up, and they could only see portions of the opposite side at intervals, and the bottom not at all. Their tent was pitched 250 feet from the edge of the crater, and during a violent squall the india-rubber floor of the tent was found to be on the point of melting, a maximum thermometer showi a temperature of 110 deg. on one side of the 725 deg. Outside it was intensely cold, and a thermometer on tent and of but 50 deg. on the other; in the middle it was the tent cord showed a minimum of 13 deg. At night they had a fine view of the crater, which has a diameter from north to south of 2000 feet, and from east to west of about 1500 feet. In the interior the walls descend to the bottom in a series of steps of precipice, and slope a good thousand feet, and at the bottom there was a nearly circular spot of glowing fire, 200 feet in diameOn the sides of the interior higher up, fissures, from which flickering flames were leaping, showed that the lava was red hot a very short distance below the surface. The height he found to be 19,600 feet. The party remained at the top for twenty-six consecutive hours, sleeping about 130 feet below the loftiest point. At first they had felt the effects of the low pressure of the atmosphere, and again, as at Chimborazo, took chlorate of potash with good effect. All signs of mountain sickness had passed away before they commenced the descent, and did not recur during the journey. Nearly five months later Mr. Whymper returned to Chimborazo, and from a second reading of the barometer at 14'028 inches, with a temperature of 15 deg. Fahrenheit, he made the height 20,489 feet, the mean of the two readings giving 20,517 feet. While on the side of Chimborazo he witnessed a magnificent eruption of Cotopaxi, ashes rising in a column 20,000 feet above the rim of the crater and then spreading over an area of many miles. Prof. Bonney had submitted the ash to microscopic examination, and found that the fineness varied from 4000 to 25,000 particles to the grain in weight, and from observation of the area over which the ash fell Mr. Whymper calculated that at least two million tons must have been ejected in this one eruption.

ter.

A TELEGRAM was read at a recent meeting of the French Academy of Sciences from M. de Brazza, who has been conducting an exploration in the region of the Ogowé and Congo, West Africa. Quite recently a French station has been founded in the upper course of the former river in connection with the International African Association. In July last, M. de Brazza: informs the Academy, he reached the Congo from this station on the Ogowé, between the river Inpaka Mpania and the river "Lawson Afrisi." Gaining the favour of King Makoko he pacified the tribes on the right bank of the Congo, and peaceOn October 3 he founded fully descended the river in a canoe. the station of Ntamo Ncoma on land ceded by King Makoko on the right bank of the Congo. M. de Brazza surveyed the route between the Ogowé and Congo; it is twelve marches in length, over a plateau of an average height of 800 metres. country is healthy, and the population dense and peaceful. In November last M. de Brazza arrived at Mdambi Mbongo, the he reached the latter's headquarters at Vivi on November 12. advanced post of Mr. Stanley, whom he met, and with whom If the new station can be maintained and victualled, it is no doubt well chosen as a starting-point for further discovery, fo. both north and south of it there are large regions of which he knew nothing.

The

AT the meeting of the Geographical Society on Monday last, Mr. E. Delmar Morgan gave some account of his journey last year to Semiretchia and the town of Kulja. Being unable to make use of the more southern line of communications, Mr. Morgan travelled by the northern post-road from Orenburg to Troitsk and Petropaulofsk, and thence to Omsk and Semipalatinsk. He then struck southwards to Sergiopol, where he was detained three weeks owing to the southern road being blocked by snow. He afterwards went to Kulja for a short time, and he also made some excursions to Issyk-kul and other places of interest. In the course of the discussion which followed the paper, Mr. Ashton Dilke, the only other Englishman

who has visited Kulja, gave an interesting account of his experiences in that region a few years back.

FEARS had been entertained by many that the expedition sent out by the Russian merchant M. Alexander Sibiriakoff to discover the North Passage by means of the steamer Oscar Dickson, on board of which M. Sibiriakoff was himself, had been lost, and M. Konstantin Sibiriakoff, his brother, had already equipped another expedition to find and assist the Oscar Dickson. In the meantime the welcome news has arrived that Alexander Sibiriakoff reached Tobolsk at the end of December. The Oscar Dickson and another ship, the Nordland, had met fresh ice near Mate-Ssale, and had retired into the Gydan Bay on the coast of Siberia, in order to winter there.

M. TARRY, a member of the French Commission for TransSaharan Communications, is stated to have discovered in the south of Wargla the ruins of a large city called Cedrada, which had been entombed by sands of the desert. This city is placed in the Valley of Wed Mya, and in the vicinity of a number of sources which in former centuries watered thousands of palmtrees. Orders have been sent to procure a set of sounding apparatus, and it is expected a large quaniity of pure water will be extracted from the earth. M. Tarry published an appeal to the local papers in order to obtain from the Government the foundation of a colony in this remote region.

DEEP-SEA EXPLORATION1

II.

4. FOOD.-The late Prof. Sars, in his remarks on the distribution of animals in the depths of the sea, asks "Whence do animals that live at depths far below the limits of vegetation obtain their food?" Bronn, Wallich, Wyville Thomson, and others have endeavoured to answer this question; but I do not think the problem has yet been satisfactorily solved. A considerable quantity of vegetable food is undoubtedly supplied from the Sargasso Sea and a similar area in the Pacific Ocean, as well as by the sea-weeds which fringe every coast. But this supply is not sufficient for the indirect support of the countless host of animals that inhabit the depths of the ocean, all of which are necessarily zoophagous or subsist on other animals. Plant life, except perhaps one of a peculiar kind, which will be presently noticed, appears to be absent in depths exceeding 150 fathoins.

In all probability the chief supply of vegetable food is derived from the countless diatoms, coccoliths, rhabdoliths, and oscillatoriæ, which are plants of a low degree of organisation, and swarm on the surface of the sea; these are swallowed by pelagic animals (such as Salpa and Pteropods, or sea-butterflies"), and the latter fall to the bottom after death, and form that flocculent or glairy mass which I have described in the Report of the Porcupine Expedition of 1869 as covering the bed of the North Atlantic at great depths.2 The preservative effect of sea water on animal tissues would stay decomposition for a long while; and Mr. Moseley ascertained by a curious experiment that it would take only about four days for a Salpa to reach the bottom at a depth of 2000 fathoms, and that the Salpa was not greatly decomposed after having remained in sea water for a month in the tropics.

When we say that vegetable life does not exist at any considerable depth, we must not forget that some kind is said to occur in great abundance even in the benthal or deepest zone. The word "benthal" is applied to depths exceeding 1000 fathoms (see my Address, which is referred to hereafter in this lecture). Shells, corals, and other organisms, are everywhere permeated by what are considered to be minute plants allied to fungi or confervæ, which form branching canals, like those of the Cliona or perforating sponge; and such canals have been also detected in all fossiliferous strata of a marine nature, from the Silurian to the present epoch. These plants, or Thallophytes, have been called "parasitic"; but they do not live on any other living thing. They can hardly serve as food for deep-sea animals, because they are never exposed. Whether they may not be a link to connect the animal and vegetable kingdoms may be a matter for further investigation.

Food is of course a very important factor as regards the size of all animals. I have noticed, in my work on "British Conchology,"

I

A Lecture by J. Gwyn Jeffreys, LL.D., F.R.S. Given at Swansea, Llanelly, and Barrow-in-Furness, in December 1880 and January 1881. Continued from p. 302.

2 See Proc. Roy. Soc. 1870, p. 420.

that Mollusca from moderate depths are generally larger than those of the same species from shallow water; but this does not seem to be the case with a species of coral obtained in the Challenger Expedition, which ranged from a depth of 30 to one of 2900 fathoms, and was very variable in size. 5. Light.-Milton tells us of the

"world of waters dark and deep."

One of the most interesting problems relating to the subject of this lecture is whether the above is a poetical idea or based on fact, as regards the absence of light in the abysses of the

ocean.

We do not know to what extent the sun's rays penetrate the sea, nor whether the bottom at all depths is absolutely devoid of light. An ingenious apparatus, which was contrived by Dr. Siemens for ascertaining the presence of light at different depths by means of highly sensitive photographic paper, has never yet been properly tried. An experiment of this kind made by Prof. Forel proved that in the Lake of Geneva, even at a depth of only thirty fathoms, the paper was entirely unaffected after protracted exposure. But the water of that lake is peculiar; it is said to be rendered less transparent by suspended and floating particles of mica brought from glacier streams, and to have thus acquired its deep blue colour. I cannot believe that the only abyssal light, if there be any, is phosphorescent.

At all events we are certain that, as regards the sea, many animals at very great depths have eyes, and that there is no absence of colour.

Cuttlefishes, which have eyes not less highly organised than our own, have frequently been obtained from depths of many hundred fathoms; they do not eat phosphorescent polypes and such small deer. Nor are the deep-sea Mollusca blind. During the Porcupine Expedition of 1869 an undescribed species of Pleurotroma from 2090 fathoms had a pair of well-developed eyes on short footstalks; and a Fusus from 1207 fathoms had its eyes at the base of the tentacles. The last-named mollusks chiefly prey on bivalves. I have taken at moderate depths, living on the same ground, closely-allied species of univalve mollusks, some of which were eyeless or blind, and others were provided with the usual organs of vision. Numerous instances have been given by the Challenger naturalists of apparently seeing as well as of apparently sightless animals taken at great depths. Prof. Semper, of Würzburg, says, in "The Natural Conditions of Existence as they Affect Animal Life" (1881), "Many creatures furnished with well-constructed eyes live associated with the actually blind species, and which have been partly enumerated above. He mentions among the former five species of fish (one depths of from 675 to 2040 fathoms, besides several Mollusca of a new genus) discovered in the Challenger Expedition at and Crustacea.

"

Some land-slugs and mollusks (e.g. Geomalacus maculosus and Achatina acicula) are also blind. On the sea-shore and in shallow water most bivalves, as well as all the species of Chiton, are eyeless.

Some deep-sea animals are brightly and deeply-coloured. In colour" the Challenger Expedition shrimps "of an intense bright scarlet were obtained in very great abundance; and many Holothurians or Sea-cucumbers were of a 66 deep purple" hue. The same observation occurred to me in the Porcupine and Travailleur Expeditions.

6. Temperature.-The highest temperature of the sea-bottom observed in the Challenger voyage at depths over 1000 fathoms was 50°5 Fahr., in 2550 fathoms; the lowest was 32°1 only, in 1950 fathoms. The average bottom-temperature at great depths does not much exceed the freezing-point; but life does not appear to be affected by that circumstance. In the Arctic Expedition of 1875 I found an abundance and variety of animals in icy cold water.

7. Depth.-The average depth of the ocean between latitudes 60° N. and 60° S. is nearly three miles, or 2500 fathoms. The greatest depth which has been ascertained by sounding is five miles and a quarter, or 4620 fathoms, and occurs in the Northwest Pacific Ocean; it is nearly equal to the height of Mount Everest, the highest known mountain, in the proportion of 27,720 to 29,000 feet.

Telegraph Construction and Maintenance Company have mate8. Inequalities of the Sea-bottom.-The operations of the rially added to our knowledge of the shape and contour of the

floor of the ocean.

They have shown us that the bed of the sea is quite as uneven as the surface of the land, and that it represents the same mountains, hills, gorges, and valleys, equally

diversified in the one case by oceanic currents on the surface as well as on the bottom, and in the other by foaming rivers and gentle streams. I will give a few instances of such inequalities in the North Atlantic. While repairing in 1878 the AngloAmerican Cable, a tract of rocky ground was discovered, about 100 miles in length, in the middle of the North Atlantic, be tween 33° 50' and 36° 30′ West longitude, and about 51° 20' North latitude. Within a distance of eight miles the shallowest sounding was 1370, and the deepest 2230 fathoms, a difference of 860 fathoms, or 5160 feet; within four miles the difference was 3180 feet, and within half a mile 1380 feet. There are also the Laura Ethel Bank, with a depth of only 36 fathoms, and the Milne Bank, with 81 fathoms, both about 550 miles from Newfoundland, which is the nearest continental land. Other instances are the Josephine Bank, with 82 fathoms, and Gettysburg Bank, with 30 fathoms, the distance of the former from Cape St. Vincent being 250, and the latter 130 miles, with intermediate depths of from 1700 to 2500 fathomis. The soundings in the Bulldog Expedition also gave 748 between 1168 and 1260 fathoms, and the Valorous soundings gave 690 between 1450 and 1230 fathoms in another part of the North Atlantic and very far from any land.

A glance at the large series of diagrams of the Challenger soundings will at once serve to convince one of the extreme anevenness of the sea-bottom everywhere in the Atlantic and Pacific oceans. It would be difficult to find a greater degree of unevenness in any diagrams of the earth's surface, the total extent of which scarcely exceeds one fourth of that of the sea. Diagrams to illustrate the inequalities of the sea-bottom in the case of the telegraph cable, and the irregularities of level in a similar extent of land in the Perthshire Highlands, are placed before you.

9. Deposits.-The floor of the ocean is covered by a more or less thick layer of ooze or mud, and of clays of different sorts and colours, which is inhabited by various animals. One of these deposits is called "Globigerina"-ooze, and is widely distributed over the bed of both the Atlantic and the Pacific. Another deposit is called “Red Clay,” and is found at depths exceeding 2000 fathoms. Mr. Murray, one of the Challenger naturalists, has carefully worked out the deep-sea deposits which were observed and collected during the expedition. According to him the Globigerina-ooze occurred in the North Atlantic at fortynine stations, from depths between 780 and 2675 fathoms; in the South Atlantic at six stations, from depths of between 1375 and 2150 fathoms; and in the Pacific Ocean at twenty-two stations, from depths of between 275 and 2925 fathoms. He also mentions other deposits, viz. Coral-mud, Radiolarian ooze, and Diatomaceous ooze. Mr. Murray also says that volcanic products, such as pumice, lava, and scoriæ, as well as the peroxide of manganese, are universally spread over the bottom of the deep sea; and, in consequence of copper, cobalt, and nickel having been detected in the clays, he was tempted to suggest the presence of meteoric or cosmic dust in those deposits.

An animated, but quite amicable, controversy has of late years taken place as to whether Globigerina (from which the firstmentioned ooze has taken its name) lives only on the bottom or on the surface of the sea, or on both of them. You will doubtless ask, What is a Globigerina? It is a microscopic shell, consisting of a few globular cells, which are added together in the course of growth, the smallest cell being the original one or nucleus, and the largest being the last formed. All the cells are full of a protoplasmic substance called sarcode, which is amorphous or has no definite structure-no head, no limbs, no heart, viscera, muscles, or nerves. Its entire body is a stomach, and nothing but a stomach. The same kind of sarcode forms the living pulp of sponges, which have a horny or glass-like skeleton instead of a shell. The Globigerina is a member of an extensive and extremely variable class of invertebrate animals called Foraminifera; and this class, as well as sponges, belong to a kingdom called Protozoa, the name of which imports not that it was the earliest form of life, but that its organisation is of the very primary or simplest kind. The cells of the Globigerina are in their living state covered with the most delicate spines of comparatively great length, which are set outwards, and probably serve to keep at a respectful distance all predatory animals of an equally minute size. Between these spines some of the sarcode is occasionally, if not habitually, protruded at the will of the animal through very fine pores of the shell, which gave rise to the name Foraminifera. Such prolongations or expansions of

the sarcode are called pseudopodia, and are used for capturing and taking into the body or stomach animal or vegetable particles which serve for food, and are engulfed in the internal sarcode. Having premised thus much, and in the hope that my description may be tolerably intelligible to those who have not, like myself, studied the Foraminifera, I will proceed with my account of the controversy. I have frequently taken with a towing-net on the surface of the sea a multitude of floating Globigerina, which were certainly alive and showed their pseudopodia as well as their long and thick-set spines. Major Owen and Lieut. Palmer, who especially studied the surface-fauna of the Atlantic, observed and have published the same facts. Therefore when, in the joint report of my colleagues and myself to the Royal. Society, on the results of the first Porcupine Expedition in 1869, it was stated or strongly inferred that the Globigerina really "inhabit the bottom on which they are found in such extraor dinary abundance," and that the hypothesis accounting for such accumulation by their having fallen to the bottom after death, their lives having been passed at or near the surface, was conclusively disproved, I ventured to record my dissent from that conclusion. The observations of Mr. Murray, one of the naturalists in the Challenger Expedition, have fully confirmed the hypothesis that Globigerina lives on the surface; and Sir Wyville Thomson now admits 2 it as an established fact. But Dr. Carpenter is not satisfied. He is of opinion that "whilst the Globigerina are pelagic in an earlier stage of their lives, frequenting the upper stratum of the ocean, they sink to the bottom whilst still living, in consequence of the increasing thickness of their calcareous shells, and not only continue to live on the sea-bed, but probably multiply there-perhaps there exclusively." 3 I must say that I am not convinced by the instances and arguments which he adduced in support of his opinion. There is no question that a great many species of Foraminifera live always on the sea-bottom; but I do not know that any species of pelagic or surface-dwelling animal inhabits also the sea-bottom. Dr. Wallich found that the stomachs of star-fishes which came up with the sounding-line from 1260 fathoms con. tained fresh-looking Globigerinæ, and that the latter were full of sarcode. This does not prove much, because sea-water is to some extent antiseptic or retards putrefaction. Many star-fishes feed like earthworms, and swallow quantities of organic and inorganic matter for the purpose of extracting nutriment from it. Sir Wyville Thomson says, in his paper "On Dredgings and Deep-Sea Soundings in the South Atlantic" (Proc. R. S. vol. xxii. p. 427), that the appearance of Globigerina and certain other Foraminifera, when living on the surface, is so totally different from that of the shells at the bottom that it is impossible to doubt that the latter, even although they frequently contain organic matter, are all dead." Mr. Murray adds (Proc. R. S. vol. xxvi. p. 535) :-"No living specimen of a Globigerina, an Orbulina, a Pulvinulina, or of the new genera found on the surface, which undoubtedly came from the bottom, has yet been met with. The foregoing observations appear to justify the opinion that these organisms live only in the surface and subsurface waters of the ocean.'

I will not however presume to assert that Dr. Carpenter may not be right; but is he justified in taking for granted "that the onus probandi rests on those who maintain that the Globigerina do not live on the bottom"? It is rather difficult to prove such a negative.

The colour of the "Red Clay" was attributed by Mr. Murray to the presence of oxide of iron.

Mr. Etheridge obligingly examined some of the pebbles and minerals which I had dredged in the Valorous Expedition at depths of from 690 to 1750 fathoms. He reported that many of them were Imost likely derived from Iceland." If this were the case, the pebbles and minerals might have been transported by a deep submarine current.

The deposits in very deep water, and beyond the range of fluviatile and tidal action, are so slight as to be almost filmy, and are chiefly composed of the skeletons or hard parts of Globigerina, Diatoms, and Radiolaria. The subjacent layer of mud or ooze, where it is beyond the scope of river action, may have been formed from the ruins of a sunken continent.

The proportion of carbonate of lime contained in the deepsea mud or ooze of the North Atlantic, which was procured in the first two cruises of the Porcupine Expedition of 1869, slightly differed. In a sample from 1443 fathoms, dredged off the west I Journal of the Linnean Society, vol. ix. p. 147. 2 Proc. Roy. Soc. vol. xxiii. p 34. 3 Ibid. p. 235.