complex parts act interdependently—as the various parts of a steam-engine—yet all constituting one grand mechanism. Nature's forces respect no national frontiers; and, if their mighty play is to be watched by science, its observational corps must be expanded to cover every accessible part of the globe. This will be made more apparent if we consider the intensities and movements of cyclones. The storms generated over the sea often push with resistless energy against the loftiest mountain-walls, and, surmounting their acclivities, press on as if they had felt no retardation, to sweep across an entire continent, and then, untired, to take a fresh start on a long ocean-voyage. In a rigid examination of the Signal-Service data for a period of twenty-six months, twenty-eight storm-centers, it was found by Professor Loomis, traveled eastward across the Rocky Mountains, and reached the Mississippi Valley in unimpaired vigor, having scaled that imposing barrier, 10,000 feet high, as easily as the steamship on its rapid course overrides a wave. In discussing the two cyclones which visited the Bay of Bengal in October, 1876, Mr. Elliott, Meteorological Reporter to the Government of Bengal, incidentally gives us some idea of the cyclopean forces which are developed by such storms. The average "daily evaporation," registered by the Bengal instruments, in October, "is 2 inches."[1] The amount of heat absorbed by the conversion of this amount of water daily over so large an area as the Bay of Bengal is enormous. "Roughly estimated," says Mr. Elliott, "it is equal to the continuous working power of 800,000 steam-engines of 1,000 horse-power." A simple calculation will show that it
Vertical Section of the Heat of a Cyclone. (Arrows show direction of wind and the ascending current in storm-center; the dark-shade, nimbus, or rain-cloud.)
suffices to raise aloft over 45,000 cubic feet of water in twenty-four hours from every square mile of the bosom of the bay, and transport it to the clouds which overhang it. When we extend the calculation from a single square mile to the area of this whole Indian gulf, the
- ↑ "Report of the Vizagapatam and Buckergunge Cyclones of October, 1876," by J. Elliott, p. 182.
