Page:Journal of the Optical Society of America, volume 30, number 12.pdf/79

 twenty-four dominant wave-lengths. He studied and examined the general type of spectrophotometric curve which yields a maximum value for the visual efficiency for materials exhibiting a given chromaticity when illuminated with light of a specified quality, and presented a new proof of the validity and uniqueness of this type of curve.

“2. In a study of ‘Photometric Relationships Between Complementary Colors,’ he presented formulas and tables for the interconversion of colorimetric and excitation purities, and reviewed the complementary relations between colors having maximum visual efficiencies.

“3. In a review of the ‘Photographic Aspects of the Theory of Three-Color Reproduction,’ he examined the significance of the concept of photographic spectral sensitivity and emphasized the desirability of emulsions having contrast independent of wave-length. He also determined the limits within which it is possible or desirable to increase purity by an increase of contrast.

“4. In a report on ‘Subtractive Color Mixture and Color Reproduction’ he showed how the analytical form of a simple rule for predicting the colors of mixtures of certain dyes can be incorporated into the theory of color reproduction, and derived formulas for use in printing a subtractive reproduction, and in the simultaneous introduction of partially negative spectral sensitivities.

“5. More recently he has undertaken to investigate the ‘Noticeability of Color Difference in Daylight’ which has now culminated in a report presented at this meeting of the Society. He has developed and carried out an extensive series of color-match observations and has examined in detail the probable errors to be expected and encountered in such color matching.

“Mr. President: It gives me great pleasure, on behalf of the Committee and of the officers of the Society, to present at this time Dr. David Lewis MacAdam as a person highly qualified to receive the Adolph Lomb Medal because of his noteworthy contributions to optics.”’ After President Gibson had formally bestowed the medal, Dr. MacAdam responded briefly as follows:

“Mr. President: I realize that I must not take the time that would be necessary to express adequately my appreciation of the award which you have just bestowed upon me. May I say simply that I feel greatly honored at being chosen to receive the first award of this symbol of encouragement for young men entering the field of optics. I thank you sincerely.”

A brief business session of the Society was held Saturday morning, October 5, at 9:45 A.M., President Gibson presiding. Formal reports of the Secretary, Treasurer, and Editor of Publications for the calendar year 1939 were received and placed on file. Informal reports covering the period from January 1, 1940 to the time of the annual meeting in 1940 were also presented.

President Gibson called attention to the fact that the term of appointment of Arthur C. Hardy as Secretary of the Society would expire at this annual meeting. He also called attention to the report of a Nominating Committee, which had been circulated in accordance with the provisions of the By-Laws. On a motion from the