From what has been said it will be evident that a former toy has been proved to be of the greatest importance for meteorological investigation at the Blue Hill Observatory. On account of the success there attained it is coming into use elsewhere for meteorological observations. In 1898 the United States Weather Bureau created seventeen kite stations, chiefly in the Mississippi Valley, with the intention of obtaining data every day, at the height of a mile or more, with which to plot a synoptic weather map similar to the map that is now drawn from the data at the ground. From a knowledge of the weather conditions prevailing simultaneously in the upper and lower air, it was expected that the weather forecasts could be improved, but unfortunately, on account of the light winds during the summer, it was impossible to make enough simultaneous kite-flights to construct the upper-air map, and therefore the scheme was abandoned. However, the data obtained will no doubt furnish valuable information about the vertical temperature gradient, etc., in various conditions of weather. The chief meteorological bureaus of Germany and Russia are equipping stations with kites and balloons, and M. Teisserenc de Bort, who has provided his private observatory near Paris with kite apparatus of the Blue Hill type, has already reached high altitudes. In Scotland too, which was the birthplace of scientific kite-flying, experiments have been resumed by a Scotchman and an American--a happy union of forces. From these preparations it appears that the resolution of the International Aeronautical Conference, recommending that all central observatories should employ this method of investigation as being of prime importance for the advancement of meteorological knowledge, is being carried out, and seems likely to produce important results. CHAPTER VI RESULTS OF THE KITE-FLIGHTS AT BLUE HILL--FUTURE WORK Kites possess several advantages over other methods of exploring the air up to heights of at least 12,000 feet whenever there is wind, but their chief merit is, that with them the true conditions of the air may be ascertained. The disadvantages of other methods of exploring the air, as compared with kites, are these: 1. =Mountains= not only affect by contact the adjacent air, but by deflecting the air-currents cause mixture and ascent, which give conditions differing widely from those of the free air.