Professor Pickering's Report.

In his annual report, just issued, Professor Pickering says the Harvard Observatory astronomers have made not a few valuable and interesting discoveries. They took 2777 stellar photographs in Cambridge and nearly 2000 in Peru. By means of these no less than seven new variable stars have been discovered, and the number of stars of the fifth type has been increased by eight, making the total number forty-five. The spectrum of the nebula surrounding some of the stars is unlike that of any other gaseous nebula.

The amount of valuable material accummulated with these instruments is continually increasing, and has proved useful in many cases in studying the past history of new objects. Plates have been sent to the Lick and Amherst observatories and to the Smithsonian Institution for special investigations.

A large number of photographs were taken of the new star in Auriger. These were taken with exceedingly great care, and the results are expected to be almost perfectly accurate.

Many photographs of the lunar eclipse of Nov. 15, 1891, were taken, both at Cambridge and at the Boyden Observatory in Arequipa, Peru. The examination of these photographs for the detection of a possible lunar satellite led only to a negative result.

An extensive series of observations was also made upon Mars. More than forty minute black points were discovered, provisionally designated as lakes. The polar compression of the planet was also measured and appeared to be greater than that indicated by theory, which may be due to an excess of clouds in the equatorial regions. The presence of the dark and narrow streaks, called canals by Schiaparelli, has been confirmed, and various measurements of them have been made. The clouds projecting beyond the limb and terminator have been studied, and their height has been found to be at least twenty miles.

Stations have been established at Mallendo, 100 feet above the sea level; at La Joyce, whose elevation is 4,150 feet; at the observing station, 8,060 feet high, and at Chachani Ravine, 16,650 feet high.

The approaching completion of the new Bruce photographic telescope was referred to at length by Professor Pickering. If successful, it will be the most powerful in the world. The eight surfaces of its objective have been ground and polished so that it could be tested on a star. The results were satisfactory. Plans have been made and the foundations laid for a one-story brick building, with a sliding roof, in which it will be erected during its trial in Cambridge. After this it is proposed to send it to the Arequipa station in Peru.