96 



SCIENCE, 



[N. S. Vol. VII. No. 160» 



Harvard were made from May, 1889, to Sep- 

 tember, 1890, inclusive, and embraced those 

 made with standard, maximum and minimum 

 thermometers, rain-gauge, barograph and ther- 

 mograph, sunshine and pole-star records. 



Owing to the approach of the cloudy season 

 and to the consequent difficulty of carrying on 

 work with the meridian photometer. Professor 

 Bailey and his party left Mt. Harvard in No- 

 vember, 1889, in order to spend the succeeding 

 cloudy months in a study of the meteorological 

 conditions of other parts of the coast farther 

 south, with a view to selecting the most favor- 

 able site possible for the location of the perma- 

 nent observatory. On this trip Arequipa was 

 visited and a study made of its availability as a 

 site for the observatory. Farther south, Pampa 

 Central, in the desert of Atacama, was visited 

 and a system of observations of cloudiness 

 started, which were continued (thrice daily) 

 from December 14, 1889, to August 23, 1890. 

 In this region there is absolutely no vegetation, 

 not even the cactus growing there. Pampa 

 Central is in a rich nitrate field, and is distant 

 from the Pacific Ocean about 80 miles, its alti- 

 tude being 4,530 feet above sea-level. 



In October, 1890, Arequipa having then been 

 chosen as the permanent site for the observa- 

 tory, the Mt. Harvard station was given up. 

 The exact site of the observatory was chosen 

 by, and the buildings erected under the super- 

 vision of Professor Wm. H. Pickering, who 

 came to Arequipa in January, 1891, and re- 

 mained in charge of the station for two years. 

 Since that time Professor Bailey has been in 

 charge. 



The meteorological observations above re- 

 ferred to, made at Mt. Harvard and at Pampa 

 Central, were not the first made in Peru under 

 the auspices of the Harvard College Observa- 

 tory. By means of correspondence carried on 

 in 1887 and 1888 Professor E. C. Pickering had 

 already been able to establish four meteorolog- 

 ical stations, at which observations were begun 

 in November, 1888, viz.: Mollendo, Arequipa- 

 Vincocaya and Puno. At Arequipa observa- 

 tions have been continued from that date down 

 to the present time, and at Mollendo they were 

 continued until 1896, when the station was re- 

 moved to Mejia, a neighboring town, close to 



sea-level on the Pacific Ocean. At Puno the 

 observations were discontinued in March, 1889, 

 and at Vincocaya in November, 1890. All 

 these places are on the line of railway running 

 from Mollendo, on the Pacific, to Puno, on 

 Lake Titicaca, at an altitude of 12,540 feet. 

 The whole length of the line is 325 miles. 

 Vincocaya, at an altitude of ^14,360 feet, was, 

 at the time when observations were there made, 

 the highest meteorological station in the world. 

 It is situated on an extensive level plateau, 

 barren except for some sparse desert vegeta- 

 tion, and is very near the crest of the western 

 range of the Cordillera, the highest point on 

 the line of the railway being at Crucero Alto, 

 14,666 feet, a short distance east of Vincocaya. 

 The instruments used at Vincocaya were maxi- 

 mum and minimum and dry-bulb thermometers, 

 rain-gauge, wind-vane and thermograph, and 

 observations were also made of cloudiness. At 

 Puno, situated towards the western end of 

 Lake Titicaca, no thermograph was in opera- 

 tion. 



The meteorological stations at present at work 

 under the auspices of the Harvard College 

 Observatory in Peru are the following : 

 Mejia, La Joya, Arequipa, Pampa de los 

 Huesos, Mont Blanc, Misti Summit, Cuzco- 

 and Echarati. These stations are roughly in 

 a S.-N. line, and extend from the seacoast 

 across both ranges of the Cordillera and 

 down to 3,300 feet, in a valley at the head of 

 the Amazon river system. A brief descriptioB 

 of these stations, and of the instruments in op- 

 eration at each one, may be of interest. The 

 station at Mejia has, since January, 1896, re- 

 placed that which had existed at Mollendo from 

 1888 through 1895, and as the two places are- 

 near together, and have similar topographic 

 surroundings, the continuity of the records has 

 not been seriously interfered with. Mejia is- 

 situated on the Pacific, 9} miles from Mollendo, 

 the port of Arequipa and the terminus of the 

 railroad. The instruments are 55 feet above- 

 sea-level and 420 feet from the sea. The sur- 

 rounding country is extremely desolate, there 

 being only the most scanty vegetation, except 

 where irrigation is possible. Behind Mejia 

 there is a range of hills, barren and unattract- 

 ive, and all around it there is an abundance of 



