Another Astronomi al Expedition.

About a year and a half has elapsed since Professor Pickering of Harvard Observatory sent the first astronomical expedition, with Mr. W. H. Pickering in charge of it, will be sent to join the first. They will leave on the 20th of this mouth, travelling by way of Panma, and reaching Arequipa, near which is the observatory, about the last of January. The work will be an extension of the work done here on the Southern stars. Peru is sufficiently far south to get a comprehensive view of the southern stars, and, moreover, being a country with little rain, has a very clear atmosphere. Two new instruments will be carried down, one to photograph a map and the spectrum of the stars, the other to measure their brightness. Photographs will also be taken of clusters and double stars. The expedition will remain there for two years or more; and special preparations will be made to observe an eclipse of the sun which takes place in the spring of '93.