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Rh must admit that we are in this respect undeniably inferior to other nations. Still plunged in lamentable ignorance and regardless of the information obtained by careful scientific experiments, we ravage our coasts, and statistics show that the fishing industry is incapable of furnishing daily bread to those who practice it at the cost of so much trouble, fatigue, and danger. We profit by the sea as savages profit by the earth, when, according to the famous simile, finding a fruit tree in the forest they cut it down to gather its fruit. We have no complete and detailed map, not even a mediocre one, of the sea bottom, nor have we any exact ideas of the variations in temperature, in density, in salinity, along our coasts; we have not calculated the amount of sediment deposited by any of our great rivers; we are ignorant to what depth currents are felt and, except for a very small number of localities, as to their direction on the surface; we have no idea of their variations in intensity at different periods of the year. It is only too easy to add to this list of the data which we now lack. However full of good intention the measures of the administration may be, they are fruitless if they have not the intervention of authority to sanction the application of the measures approved by science. How can we be astonished by the poverty of our fishers and the fatal consequences which can not fail to affect the country? Fish are an important item in the economies of nations. According to statistics now somewhat old but rather increased than diminished by time, the world captures and consumes annually 2,000,000,000 francs worth of fish.

The industry of laying submarine telegraphs depends on oceanography to the same extent that the construction of railroads or canals depends on topography and continental geology. Perhaps the dependance of the telegraphs is even greater. The railroad and the cable follow the contour of the soil; both, for analogous reasons, must avoid too irregular ground, and the nature of the bottom is of the utmost importance. On certain bottoms swept by currents, as on the Wyville Thomson reef to the north of Scotland, the cable, subject to continual vibrations against the pebbles or frayed by their unceasing friction as they are washed about by the movement of the waves, wears out and breaks, however solid its envelope may be. At other times, on volcanic bottoms, as near Greece, for example, or in the Malay Archipelago, the cable may be stretched by displacement of the ground, causing changes in the level which break it.

The landing of the cables is no less important. Rocks are always very dangerous if they are situated in the zone of action of waves and tides. While in the open sea the land has every chance of being uniform, near the coast it often becomes irregular. It presents sudden declivities or deep hollows, reefs, straight crevasses bounded by almost perpendicular walls, such as M. Pruvot has recently discovered, not in some unknown corner of the Pacific or the South Sea, but in the