chiefly on the self-recording instruments of Richard Fréres. The station was established by the writer in 1893, and was visited later by different members of the observatory, or by some person engaged especially for the purpose. At such visits the observer rewound the self-recording instruments and made personal observations. This station was continued for about seven years. The records were broken, and not always of the highest accuracy, but it is believed that they will be of service to meteorology. Personal observations of the highest precision at this station are much to be desired, but a special gift for this purpose would be necessary. Few persons could live, even for a few days, at such an altitude. Nearly every one suffers from mountain sickness, and sometimes very severely. Nevertheless, there are sufficiently well educated persons, born in Peru at a high altitude, who could be engaged for a reasonable sum to pass alternate weeks at the summit. In this way, for a few thousand dollars, complete records of great precision and value to science might be obtained. There are also problems in astronomy and physics, which could be investigated at a well-equipped station at such an altitude, which perhaps can never be solved at sea-level.
Arequipa is a city of about thirty thousand inhabitants. It lies on the western slope of the Cordillera at an elevation of seven thousand five hundred feet. No more beautiful view can well be imagined than that which is seen as one approaches Arequipa from the coast. It is built of a soft white volcanic stone, and in the distance appears to be a city of marble. It is surrounded by wide-spreading green fields of wheat, corn and alfalfa. It is in a region of volcanoes and earthquakes, but the danger from these is slight, either to observers or to instruments. The observatory is situated on rising ground, about two miles north of the city, at an elevation of eight thousand feet above sea-level. To the north rises the great range Chachani, about twenty thousand feet in elevation; to the northeast El Misti, a volcanic cone nineteen thousand feet high; and to the east Pichu-Pichu, over seventeen thousand feet high.
The climate of Arequipa is superb for those who do not object to a somewhat rarefied and dry atmosphere. There is scarcely any seasonal change in temperature during the year, though the diurnal range is fairly large. The mean maximum and minimum temperatures for the year 1902 were 68° and 49°. In the observatory residence, which is built of stone, the temperature without artificial heat ranges between 60° and 65° Fahrenheit. The rainfall is slight, amounting to only two or three inches during the year. Agricultural pursuits are possible only by means of irrigation. Around the fertile fields, in whose center lies the city, extend endless barren pampas. All the waters of the Chili River, however, are now well utilized, and there is no other convenient supply.
