| A | B | C | D | Total. | |||
| 1890. | January. | Pampa Central | 21 | 7 | 0 | 1 | 29 |
| " | " | Mount Harvard | 0 | 2 | 2 | 27 | 31 |
| " | February. | Pampa Central | 12 | 12 | 1 | 3 | 28 |
| " | " | Mount Harvard | 0 | 0 | 0 | 28 | 28 |
A record of the cloudiness was kept not only at Mount Harvard, but at Arequipa and Pampa Central for some time after our residence in Chili. The cloudy season at Mount Harvard and Arequipa is in the southern summer, that of Pampa Central in the southern winter. By changing from one to the other of these localities one could keep in a region of clear sky nearly the whole time.
As a result of the investigations thus made the director selected Arequipa for the site of the permanent station, and the equipment on Mount Harvard was removed to that, city in October, 1890. In January of the following year Professor W. H. Pickering arrived in Arequipa, bringing with him the thirteen-inch Boyden telescope and other smaller instruments. Under his direction a residence for the astronomer in charge and his family was erected, and two additional buildings were received from the United States. One of these was designed for a laboratory and the other for the use of the Boyden telescope. During his two years' residence in Arequipa, Professor Pickering, assisted by Mr. Douglass, made a large number of observations of Mars, and of the satellites of Jupiter and Saturn, as well as of the
