There is also a meteorological observatory on Mont Blanc, but it is not at the summit and is not quite so high as that on Monte Rosa. The solar observatory which once stood at the very top of Mont Blanc no longer exists. The United States Signal Service (now the Weather Bureau) formerly maintained observatories on Pike's Peak (14,134 feet) and Mount Washington (6,280 feet). The loftiest of meteorological stations was, however, that formerly operated by Harvard College Observatory on the summit of El Misti, Peru (19,200 feet). For a number of years the United States Weather Bureau maintained a large and important observatory at Mount Weather, at the crest of the Blue Ridge, near Bluemont, Virginia. In the Old World one of the most famous of mountain meteorological observatories was that which stood on Ben Nevis (4,406), the highest summit in the British Isles. This was closed in 1904. If the conditions of life at these high-level stations are such as to repel any but the ardent lover of science, the same is true in even greater measure of those endured by the little band of meteorologists who man the observatory maintained by the government of Argentina at Laurie Island, in the South Orkneys, on the verge of the Antarctic. Every year a party of four is sent out from Buenos Aires to spend a year of exile in this inhospitable spot, which is generally ice-bound, and has not even wireless communication with the rest of the world. This station has been in operation since 1904. The staff, which is changed each year, has embraced men of several nationalities--Scotch, American and others. Far within the Arctic Circle two meteorological observatories are maintained in Spitsbergen; but these are, at least, connected with the world by radiotelegraphy. If the hopes of explorer Peary are accomplished, an observatory will, one of these days, be established at the South Pole. [Illustration: LAUNCHING A METEOROLOGICAL KITE] THE AIR ABOVE US Monograph Number Five in The Mentor Reading Course Meteorologists are not content to limit their investigations to the stratum of air lying close to the earth's surface. Even before the demands of the aeronaut for information concerning the structure and phenomena of the atmosphere far overhead became pressing, many efforts had been made to secure such information, in view of its important bearing upon many scientific problems. As long ago as the year 1784 a balloonist, equipped with various meteorological instruments, made an ascent from London and brought back an interesting series of observations, which were communicated to the Royal Society. For more than a century the manned balloon was the principal means of sounding the upper atmosphere.