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Under these circumstances, the dredging and the care of the specimens were unusually tiresome otherwise our enthusiasm would, per

700 fathoms has, therefore, been deferred until the completion of the Albatross.

In addition to the three trips made in 1880, seven trips were made by us in 1881 from Wood's Holl, and in 1882 five trips. During these fifteen trips, on each of which a single entire day was usually employed in dredging, we occupied about 113 stations. At nearly all these stations we used a large beam-trawl of improved construction (fig. 1). In a few

FIG. 1. The beam-trawl. The length of the beam, a, a, varies from 12 to 15 feet in those used by us. The height of the iron runners, b, b, supporting the beam, varies from 24 to 30 inches; the length of the net, d, from 25 to 35 feet or more. The pockets, e, within the net, are to prevent the escape of fishes. The drag-rope, c, c, is weighted with lead sinkers.

haps, not have allowed us to retire, even at midnight. But a touch of genuine seasickness will dampen the ardor even of the most enthusiastic naturalists when hundreds of new and strange species are before them.

This first trip having been so successful, two others were made, later in the season, to other parts of the slope, in depths ranging from 85 to 500 fathoms. Each trip proved equally productive, and added many species to the long list of discoveries.

In 1880 the headquarters of the fish-commission were at Newport, R.I.; but in 1881 and 1882 they were at Wood's Holl, Mass., where a laboratory had already been fitted up in 1875. In 1881 and 1882 the exploration of the Gulf Stream slope was continued, whenever the weather was sufficiently favorable to permit us to make a trip in the Fish Hawk without too much risk.

The steamer Fish Hawk, with which we have explored this region during the past three seasons, was built particularly for use in the hatching of shad-eggs in the mouths of shallow rivers, and was therefore not adapted for service at sea, unless in fine weather. A much larger iron steamer - the Albatross, of 1,000 tons has recently been built for the use of the fish-commission, and is now being fitted up expressly for deep-sea service, for which she will be in every respect well adapted, and will have the best equipment possible for such investigations at all depths. The examination of the bottom beyond the depth of about

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nets (fig. 3), were used to capture freeswimming animals, whenever the motion of the steamer was sufficiently slow to permit

FIG. 3. The towing-net, in the position that it takes while in use, half buried beneath the surface of the water. Those used by us are mostly 10 to 14 inches in diameter.

this mode of collecting. In these towing-nets, and in long-handled dip-nets, we secured a great variety of pelagic creatures, such as jelly-fishes, Salpa, Sagitta, various small Crustacea, and especially large numbers of Ento

mostraca.

Our dredgings in this region now cover a belt about 160 miles long, east and west, and about 10 to 25 miles wide. The most eastern stations are south-east of Cape Cod; the most western are south of Long Island. They are mostly between 80 and 110 miles from the coast-line of southern New England (see map, p. 444). The

regular work of the party during the season, Capt. Tanner made a special trip to the Gulf Stream slope, off Chesapeake Bay, in 1880, and another off Delaware Bay in 1881. On both of these occasions valuable collections were made, and additional data in regard to the depth and temperature were obtained. He occupied seven stations, in 18 to 300 fathoms, in 1880; and eight stations, in 104 to 435 fathoms, in 1881. These dredgings show the direct southward continuation of the inshore cold belt, and the warm belt outside of it, as well as the cold deep-water belt, with but little change in the fauna of each.

2. Physical features of the region. The total number of species of animals already obtained by us from deep water in this area is not less than 800. The number already identified or described, and entered on our lists of the fauna, is about 650. This number includes neither the Foraminifera nor the Entomostraca, which are numerous, and but few of the sponges. Of this list, less than onehalf were known on our coast before 1880, and a large number were entirely unknown to science. Of fishes there are, perhaps, 70 species. Of the whole number, already determined, about 265 are Mollusca, including 14

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DIAGRAM 1. To illustrate the relative slope or profile of the bottom, from the shore to the Gulf Stream slope, and across portions of the slope in several lines. Vertical to horizontal scale, 1: 360. The line n'-o' shows the actual slope along the line n-o. The vertical shading indicates the position of the comparatively warm water, both of the surface and of the Gulf Stream; oblique shading to the right indicates the cold water of the shallow plateau; oblique to the left, the cold water of the greater depths.

depths are mostly between 65 and 700 fathoms. Probably no other equally large part of the ocean basin, in similar depths, has been more fully examined than this. In addition to the

Cephalopoda; 90 are Crustacea; 60, Echinodermata; 35, Anthozoa; and 65, Annelida.

The apparatus used on the Fish Hawk has been better in many respects than most other

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vessels engaged in such work have had. Each year new improvements have been made. The trawl-wings,' first introduced by us in 1881, have been used with great success; for they have brought up numerous free-swimming animals from close to the bottom, which would not otherwise have been taken. The use of steel wire for sounding, and of wire rope for dredging, has enabled us to obtain a much greater number of dredgings and temperature observations than would have been possible under the old system of using rope, employed even on the Challenger. The use of steelwire rope for dredging, first invented by Mr. A. Agassiz, and very successfully employed by him on the Blake, has proved to be an improvement of very great value in deep water. By its use there is an immense saving of time, and consequently a great increase in the value of the results. As an illustration of the rapidity with which dredging has been done on the Fish Hawk by using the wire rope reeled upon a large drum, I give here memoranda of the time required to make a very successful haul.

In 640 fathoms, at station

No. 1124, the large trawl was put over at 4.29 P.M.; it was on the bottom at 4.44, with 830 fathoms of rope out; commenced heaving in at 5.17; it was on deck at 5.44 P.M.; total time for the haul, 1 hour and 15 minutes. The net contained several barrels of specimens, including a great number and large variety of fishes, as well as of all classes of invertebrata, -probably more than 150 species altogether, many of them new.

At all the localities that we have examined, the temperature of the water, both at the bottom and surface, was taken, as well as that of the air. In many cases, series of temperatures at various depths were also taken. Many other physical observations have also been made and recorded. Lists of the animals from each haul have been made with care, and arranged in tables, so far as the species have been determined up to date.

South of New England the bottom slopes very gradually from the shore to near the 100-fathom line, which is situated from 80 to 100 miles from the mainland. This broad, shallow belt forms, therefore, a nearly level, submarine plateau, with a gentle slope seaward. Beyond the 100-fathom line the bottom descends rapidly to more than 1,200 fathoms into the great ocean-basin, thus forming a rapidly sloping bank, usually as steep as the slope of large mountains, and about as high as Mount Washington, New Hampshire. This is well shown by diagram 1, which illustrates the

relative slope at several lines of dredging, and the actual slope n'-o' along the line no. We call this the Gulf Stream slope, because it underlies the inner portion of the Gulf Stream all along our coast, from Cape Hatteras to Nova Scotia. In our explorations a change of position of less than 10 miles, transverse to the slope, sometimes made a difference of more than 3,500 feet in depth. [To be Continued.]

THE INTERNATIONAL FISHERIES
EXHIBITION.

Ir is just thirty-two years, nearly the third part of a century, since international exhibitions were inaugurated. The Great exhibition of 1851 marks an epoch in the history of England. It brought with it new aspirations for culture, and new methods of education in science pure and applied, in the arts aesthetic and industrial, arousing them to a new intellectual life. "The Great exhibition of 1851," remarks a popular novelist, a social philosopher as well, did one great service for country people it taught them how easy it is to get to London, and what a mine of wealth, especially for after-memory and purposes of conversation, exists in that big place.' It gave them the great treasure-houses of South Kensington, and the smaller kindred museums in all parts of the United Kingdom.

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The world at large has profited by the same experience, though perhaps to a less degree. Every nation, almost every great city, has had its world's fairs,' and, according to its capacity, has profited by their lessons. It is doubtful whether we shall ever see another universal exhibition so extensive as those of Philadelphia (1876), of Vienna (1873), and of Paris (1867). The ideal has become too lofty; and the exhibition of to-day, like the worker, must be devoted to a specialty. The fisheries exhibition, soon to open at South Kensington, is as nearly as possible upon the site of the exhibition of 1851, and covers precisely the same area of ground; namely, twenty-one acres. It would be instructive to estimate how large an extent of territory would be covered by an exhibition in which should be represented, with the minuteness of to-day, all the divisions of the classification of 1851, a classification, which, for minuteness, comprehensiveness, and philosophical system, has not since been equalled. An entire English shire would hardly suffice.

Special exhibitions have probably entirely superseded those of general scope, and their number is yearly increasing. In one year, re

cently, the government of Austria participated in fifteen. Amsterdam, Zurich, Lisbon, Hamburg, Vienna, Madras, and Tokio, among others, have exhibitions of varying scope now in progress, or soon to open.

The fisheries exhibition is an institution at the success of which even the most sanguine seem to be astonished. No one has yet propounded a theory which explains satisfactorily the reason why these exhibitions succeed, yet succeed they do, perhaps more fully than special exhibitions of any other kind; and, moreover, they seem to enlist the interest of a larger number of scientific workers than do other exhibitions, though, of course, the electrical, geographical, and meteorological exhibitions are attractive in a higher degree to the students of those individual specialties.

The Berlin fisheries exhibition of 1880 was largely under the control of specialists in science. Among its most active supporters were men like Virchow, Peters, Magnus, Hilgendorf, Dohrn, Möbius, Von Siebold, Nitsche, Oscar Schmidt, H. A. Meyer, Wittmack, and Jäger, almost all of whom were on the board of direction; while, as commissioners and jurors, Italy sent Targioni-Tozzetti, Giglioli, Ricchiardi, Pavesi, Vinciguerra, and Cavanni, in short, all her marine zoologists; Bohemia, Fritsch; Denmark, Lütken; Russia, De Solsky and Grimm; Norway, Raasch and Collet; and Sweden, Smitt, Thorel, and Malm. It is not difficult to understand why a statesman, diplomatist, and political economist like Professor Virchow should be willing to give up his days and nights for two months to committee and jury meetings, when it is remembered how much stress Germany places upon all which relates to the food-supply and the economy of all natural resources; but other interests must have influenced men like Von Siebold and Peters.

A similar array of names known to science appears in the prospectus of the London exhibition. Among the vice-presidents are the Duke of Argyll, Lord Walsingham, Sir John Lubbock, Professor Huxley, Dr. Gunther, and Mr. Spottiswoode, several of whom, together with Professor Flower, Mr. Robert H. Scott, Sir Philip Cunliffe Owen, and Mr. Saville Kent, are members of the general committee. seems a little remarkable, however, to see the name of the president of the Royal society standing at the very tail of the list of vicepresidents, followed only by The prime warden, wardens, and court of assistants, of the fishmongers company." At the other extreme is placed H. R. H. the Duke of Edinburgh.

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James Russell Lowell, Esq., is also a vicepresident, his name standing between those of the Duke of Westminster and the Marquess of Salisbury.

Among the foreign commissioners are Prof. F. A. Smitt of Stockholm, R. Trybom of Lund, and Dr. Malm of Gothenburg, Professor De Solsky of St. Petersburg, Professor Hubrecht and Baron Von Hert of Utrecht, Professor Giglioli of Florence, Professor Nitsche of Tharandt, and Dr. M. Lindeman of Bremen. Surgeon-Gen. Francis Day is acting as commissioner for India.

An examination of the classification of the exhibition discloses the nature of the tie which binds together the varied interests represented in the lists of names which have been quoted. The ethnologist and the mechanician, as well as the fisherman, are concerned in the fishinggear and the fishing-craft of all nations;' the meteorologist and the pharologist, as well as the philanthropist, in the life-saving apparatus of all kinds;' the physicist, as well as the navigator, in the "compasses, barometers, telescopes, lights, lamps, fog-horns, systems of signalling, electric lights, luminous paint and other equipments of fishing-vessels," and in "methods of communication from the shore to lightships and fishing-fleets by submarine cables, telephone, or other means of signalling;" while the geographer and geologist find something to interest them in the charts and relief-models of the ocean and its bottom. The chemist, the sanitarian and physiologist, as well as the merchant, transporter, and manufacturer, are touched by the section which illustrates the preparation, preservation, and utilization of fish, and the food, apparel, and dwellings of the fishermen. The jurist, the statesman, and the historian may study the "History and literature of fishing, fishery-laws, and fish-commerce." Biologists of every class must study classes IV. and V.; for the word 'fish' is broadly interpreted, and is held to signify any creature living in the waters: to wit, as enumerated, a, Algae, to be arranged under genera and species, with localities appended; b, sponges in their natural state; c, corals in their natural state, polyps, jelly-fish, etc.; d, entozoa and epizoa; e, mollusca of all kinds; ƒ, star-fishes, sea-urchins, holothurians; g, worms used for bait, or noxious; leeches, etc.; h, perfect insects, and larvae of insects, which are destroyers of spawn, or serve as food for fish; i, crustacea of all kinds; k, fish of all kinds; 1, reptiles, such as tortoises, turtles, terrapins, lizards, serpents, frogs, newts, etc.; m, aquatic and other birds hostile to fish or fishing; n,

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