The month was above average for observing, there being 18 nights on which 85 spectra were secured with a total observing time of 120.8 hours. The eleven-year average shows 16 nights, 148 plates and 103.8 hours.
Approximately 744 persons visited the observatory during the month.
Director J. S. Plaskett was busy making least squares solutions of galactic rotation and preparation of three addresses relative to high temperature stars for delivery at Philadelphia, Boston and London. Gave two seminar talks on the same theme. Usual administrative duties until leaving on the 30th
[Plaskett attended the meeting of the American Philosophical Society in Philadelphia, Ed.]
Sun, Apr 6, 1930 – Page 43 · The Pittsburgh Press (Pittsburgh, Pennsylvania) · Newspapers.comAssistant Director W. E. Harper worked 7 nights obtaining 43 plates. Measured for radial velocity 40. Determined period of HR 3352 and made least squares solution od orbital elements. Gave one seminar talk and a couple of addresses outside
Astronomer J. A. Pearce observed 2 nights, obtaining 12 spectrograms. Spent month computing the motions of the O and B type stars. Determined the solar motion, K term and galactic rotation for 680 stars.
Astronomer C. S. Beals worked 9 nights, obtaining 12 plates. Focussed and adjusted ultra-violet spectrograph with new lenses. Studied radial velocity curve of Z Ursa Majoris. Continued work on laboratory spectrophotometry.
Computer S. N. Hill measured 5 spectrograms of binary HD 185396 for radial velocity. Further investigation of period for binary mentioned above. Computational work on B stars. Preparing graphs of distribution of O and B stars.
Clerk-Stenographer Miss L. M. Blake did the envelopes for 85 spectra, accounts, reports and correspondence. Typing lectures and tables for lantern slides.
Astronomical Assistant T. T, Hutchison assisted in observing on 5 nights. Kept telescope in running condition.