to a large extent by other subjects, and consequently, although the course in meteorology continues to be offered at the present in the Department of Geology, the demand for it has undergone a slight decline. The subject has recently been taken over by Ralph Leroy Belknap ('23e, Sc.D. '29), Assistant Professor of Geology, who has worked two seasons in Greenland on upper-air circulation (see Part III: Department of Geology) .
During the directorship of Asaph Hall, Jr., 1892-1905, meteorological records were continued, and were sent to the Michigan State Board of Health. In 1905 this board discontinued its meteorological work. William Joseph Hussey, Professor of Astronomy and Director of the Observatory from 1905 to 1926, adopted the system of meteorological observations of the United States Weather Bureau, and in 1907, upon his recommendation to the Regents, President Angell took up the question and secured the establishment of a United States Weather Bureau station at the Observatory. Some of the old meteorological instruments needed repair — for example, a heavy wind had carried off the anemometer balls and had broken the shaft. New instruments were also purchased to complete the equipment necessary to make records in accordance with the government requirements. The work of the station has continued to the present time.
Necessary changes have been made in the time and method of recording the observations. To 1905 they were made at 7:00 A.M., 2:00 P.M., and 9:00 P.M., in accordance with the method adopted by the Michigan State Board of Health. The Weather Bureau observations, made twice a day, at 7:00 A.M. and 7:00 P.M., include barometric pressure, air temperature, relative humidity, direction and velocity of the wind, precipitation, and cloudiness. Records are also kept of the daily maximum and minimum temperatures and of such extraordinary phenomena as severe thunder and lightning, dense fogs, heavy frosts, ice storms, dust storms, auroras, and seismic disturbances.
Regarding meteorological equipment, Hussey stated in 1912:
At the present time, as the hygrograph is not in use, the relative humidity is determined twice a day with the use of a wet- and dry-bulb sling psychrometer. The other instrumental records have been continued to the present time.Continuous instrumental records are also obtained of the velocity of the wind, as recorded by the anemometer; of the air temperature by a Richard thermograph; of the relative humidity by a Richard hygrograph and of the atmospheric pressure by a Richard aneroid barograph.
The regular meteorological observations are sent each month to the Lansing station of the United States Weather Bureau. From April 1 to September 30 each year the daily observations are telegraphed each morning to the Chicago station for the use of the Corn and Wheat Section. During the winter season a weekly report of the average depth of snow is sent to Lansing. Each morning a weather report is telephoned for publication in the Ann Arbor Daily News. The Observatory is thus continuing to contribute valuable public services through the use of its meteorological equipment.
The meteorological work at the Observatory is now conducted on the basis of a volunteer station. Because of the nearness of two primary Government Weather Bureau stations the relative value of the local work is not as great as it was in the time of Harrington.
