254 HIGHEST METEOROLOGICAL STATION IX THE WORLD. 



Southeast of and about 3,400 feet below the fsuininit is a cirque^ forming 

 a plateau less than half a mile s(|uare, Avlii<^h drops several hundred 

 feet in a precipice on the south. Near the brink, at an elevation of 

 10,650 feet above the sea, is the meteorological station. The instru- 

 ments are contained in a small louvred shelter, 22 inches square, placed 

 on a rock, and comprise the "exposed" and maximum and raininuim 

 thermometers of the U. S. Signal Service i)atteru, a self-recording ane- 

 roid barometer, and two self-recording thermometers, all of the well- 

 known liichard freres^ construction. The record cylinders revolve in 

 rather more than seven days, but as the clock movements operate dur- 

 ing ten or twelve days, records for this length of time can be obtained, 

 since, as the cylinders do not turn in an even number of days, tl e 

 diurnal variations of pressure and temperature^-during the second week 

 are not superposed up(m those of the first week. Near the shelter has 

 been erected a stone hut, where the person who ascends the mountain 

 to care for the instruments can spend the night if necessary. The 

 ascent of 8,000 feet from the observatory can be made by mule in about 

 eight hours; and though it is intended to have one of the assistants 

 visit the station each four weeks, regular ascents have not ])een prac- 

 ticable; conseijueutly, during the year the station has been equipped, 

 only portions of ten months' records could have been obtained, and 

 unforeseen stoppages of the self-recording instruments have farther 

 reduced the (quantity of complete records to eight. The automatic 

 traces of atmospheric pressure and air tempeiature are controlled by a 

 mercurial ])arometer carried up by the observer and by readings of the 

 "exposed" and the maximum and minimum thermometers, the two 

 latter showing the extremes of temperature which have occurred since 

 the last visit. The distance in an air line from the station to the observa- 

 tory is about 11 miles, and such is the transparence of the air that on 

 a large white disk, which has been placed on the edge of the i)lateau, a 

 black spot, 1 inch in diameter, can be seen with the 13-incli telescope 

 at the observatory. 



The meteorological equipment of the observatory is quite complete; 

 and besides the ordinary instruments for direct observations there are 

 the self-recording barometer and thermometer, of Richard freres, an 

 anemograph of the Signal Service type, and photographic sunshine 

 recorders of the form devised by l*rof. Pickering. Direct observations 

 three times a day, at 8 a. m., 2 and 8 r. m., with frequent night observa- 

 tions at 2 A. M., have been made during two years but have not been 

 reduced. The results of the observations at both stations will be pub- 

 lished later in the A)inals of Horranl CoJJege Olhscrratory, and their 

 discussion will no doubt add greatly to our knowledge of mountain 

 meteorology. Anything more than a brief summary of some of the 

 most salient features would, therefore, be out of \)]i\rv here. From data 

 for the year 189l-'02, cited by Prof. Pickering in Astrouomi/ and 

 Astro- Phyaics^ May, 1802, it appears that the atmospheric pressure and 



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