Page:Popular Science Monthly Volume 16.djvu/314

296 daily precipitation within the areas of storms like those just referred to is only three inches, it is evident that Mr. Elliott's calculation of the mechanical force daily exerted in the work of evaporation falls short of expressing the force exerted in the work of precipitation during a day's march of a cyclone. The latter is, however, but one of the many tremendous agencies engaged in the development of a storm of ordinary magnitude in the intratropical regions. In the extratropical and high latitudes, cyclones are much more extensive, "being seldom less than 600 miles in diameter, but oftener two or three times that amount, or even more" (Buchan); while the waves of the sea, driven by their winds, beat upon the seacoast, as Mr. Stevenson, the well-known English engineer, has estimated, with the almost incredible force of "6,000 pounds on the square foot." In the hurricane of last August, the winds on the North Carolina coast blew at the rate of from 138 to 165 miles an hour.

In citing these illustrations of the storm-phenomena which modern meteorology is charged with investigating, we have not alluded to the equally important yet far grander phenomena of "anti-cyclones," or those "atmospheric waves" of high pressure which, emanating from the higher latitudes, submerge a whole continent at once--around whose borders cyclones move as diminutive eddies playing around a rock in mid-stream. But enough has been said to show the imperative necessity for the prosecution of wide-extended or international research.(including of course oceanic observations) if the laws of weather are ever to be discovered and defined. In no branch of physics is it so true, as in that of weather-lore, "a little learning is a dangerous thing." An approximation to the conception and study of the atmospheric machine as a unit is the sine qua non of all future advance in this knowledge. Phenomena such as we have just glanced at, by their immensity and by the intensity of the forces which resistlessly propel them across seas and continents, will for ever defy adequate investigation, save by an army of observers, acting simultaneously, both on the ocean and on the land, whose outposts stretch from the rising to the setting sun and from the equator to the polar circle. For, as another has so forcibly and felicitously said: "The atmosphere, unlike the ocean, is undivided and uninterrupted; and every change of state, in any part of its expanse, sends forth a pulsation of energy which is speedily felt far and wide." If the oracles of Him by whom are all things declare that he spreads "the cloud of dew in the heat of harvest," who "gathereth the winds in his fists," and once hushed the roar of the Galilean tempest, well may these wonders, ever fresh from his hand, enlist the earnest and inspiring study and observation of intelligent men everywhere. Our favored planet, not like the airless moon, is folded in the kindly bosom of an atmosphere which, while ministering nourishment to man and accommodating itself to all his movements and vicissitudes, interposes as his shield against the fiery influences of the solar system, even to