This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1894 edition. Excerpt: ...say, 500 fathoms of the surface. I remember that when the Valorous ran a line of soundings across the North'Atlantic in August, 1875, we got 1,860 fathoms on one day, 1,450 on the next, and only 690 on the next, bringing up pieces of black volcanic stone. On the two following days the depth increased to 1,250 and 1,485 fathoms. Here there was clearly either a volcanic peak or a ridge; and wherever these are known to occur I think that it would be very desirable to explore the surrounding ocean bed and ascertain their extent and character. We want also the establishment of a more complete study of the system of ocean currents by a very extensive use of floats adapted to swim at various depths, and also a fuller investigation of the temperature and density of the water surrounding the shores of all the continents. The work hitherto done in the North Sea and the neighboring Atlantic is practically confined to the summer months, and a detailed examination at all seasons is needed. Such work is now being done under the auspices of Profs. Petterssen, of Sweden, and Mohn, of Ohristiania, Kriimmel, of Kiel, and the fishery board of Scotland. We also require a determination of the isotherms and isobars on land and sea at all seasons, which will primarily involve prolonged observations in the South Polar region, and a more 0I_I1plete knowledge of the variation of atmospheric pressure with hfilght, and its independent variation in different horizontal planes. Such an investigation embraces the whole question of the use of the bflfvlneter or boiling-point thermometer in measuring heights. This will conclude my enumeration of the geographical desiderata in the field. It is a long and formidable list, aflording work for many decades f Years to...