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The Voyage of the Challenger.
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the complete results can be published. From the address of Sir Joseph Hooker, at the recent anniversary of the Royal Society, we learn that the publication of the biological results of the Expedition have been arranged for by the Lords of the Treasury in communication with the Council of the Society, and the munificent sum of £25,000 placed at Sir Wyville Thomson's disposal for bringing them out with a completeness and in a form worthy of the expedition and the nation. Sir W. Thomsen has, with the approval of the Council and the Government, chosen for his collaborators the ablest living specialists, and this irrespective of their nationality, Our own country has, with but few exceptions, supplied entirely competent and willing workers in most of the departments, while their association with such naturalists as Agassiz and Hæckel cannot fail to be gratifying to themselves and assuring to the public.

The primary object of the expedition was, as our readers are aware, to explore the conditions of the deep sea, and the staff consequently took every possible opportunity of making deep-sea observations, and in these volumes the results achieved are recorded with such care and exactitude as to make them most valuable and instinctive to men of science, and yet so pleasingly and with so much that may be described as of a popular character, as to make the volumes available for, and enjoyable by, those who read mainly for pleasure. The dredgings were made in the greatest depths, and also from time to tine in shallow water in the most remote regions, and thus many undescribed animal forms were acquired; collections of land animals and plants were likewise made on every available occasion, and consequently naturalists of all kinds will find in these pages matter of interest to them.

From the time when the "Challenger” left Sheerness, on December 7th, 1872, to her arrival at Spithead on 24th May, 1876, she traversed a distance of 68,890 nautical miles, and at intervals about 120 miles apart 362 observing stations, of which nearly  200 were in the Atlantic, were established, The observations made at each of these Were, as far as circumstances would admit, the following, after the position of the station had been ascertained:—1.—The exact depth was determined. 2.—A sample of the bottom, averaging from 1oz, to 1lb, in weight, was obtained, 3.—A sample of the bottom water was secured for physical and chemical examination. 4 —The temperate was determined. 5.—Generally a fair sample of the bottom fauna was obtained by dredge or trawl, 6.—The fauna of the surface, and of intermediate depths, was examined by the use of the tow net. 7.—A series of temperature observations were made at different depths from the surface to the bottom. 8.—Samples of sea water were obtained from different depths. 9.—Atmospheric and other meteorological conditions were carefully observed and noted. 10—The direction and rate of the surface current was determined. 11.—At a few stations an attempt was made to ascertain the direction and rate of movement of water at different depths.

Of the many points on which the expedition haw thrown light, we can only select a few for this notice. Many of our readers will, no doubt, recall the discussions which have taken place as to the origin of the portion of sea-bottom covered with what is known as "globigerina-ooze," or "modern chalk," which consists usually of a creamy surface layer, made up of little else than the shells, most of them almost entire, of Globigerina, Pulvinulina, and Orbulina, With a relatively small proportion of finely divided matter, consisting chiefly of coccoliths and rhabdoliths, and a still smaller proportion of the spines and tests of radiolarians and fragments of the spicules of sponges, &c. Below this layer occurs another, an inch or two in thickness, somewhat more firm in consistence, in which most of the shells of all kinds are more or less broken up, and their