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 plying assistance and material for use in studies of scientific color interest. She has continued the assistance given by Mr. Spry to the subcommittee of the Colorimetry Committee of this society on the smoothing of the Munsell data. And Mr. Carlson, without whose steady eye and hand it would be hard to imagine a satisfactory supply of all of the regular and special Munsell colors that have been made since 1912, is still painting Munsell colors, although from 1931 to 1939 he was not regularly employed for full time by the company. At the present time, Mrs. J. E. O. Munsell is making provision for the development of special colors which is helping to keep Mr. Carlson with the company. Only Mrs. Bellamy and Mr. Carlson now remain of the earlier group. But the fact should be noted that a large proportion of the others connected at one time or another with the Munsell work are now employed in a wide variety of color activities. Working with the Munsell company never narrowed oneto the confines of a single “system”; rather it encouraged a broad outlook on the entire color field.

Applications of the Munsell system in scientific work have been made to a greater extent from outside the Munsell laboratories than from within.

In March, 1927, the writer was employed by the United States Department of Agriculture to develop and carry on certain adaptations of the Munsell system for purposes of color measurement that had been started in connection with hay standards and color scales for meat grading. The development of a disk type colorimeter followed, the actual spinning of disks being eliminated by spinning an optical rhomb or wedge in one side of the viewing beam. The first instrument, suggested by one made by Carl W. Keuffel as the answer to an early discussion by Priest, Munsell, and Keuffel as to whether a spinning optical part could be used for mixing colors, was developed for the Department of Agriculture through the cooperation of Mr. Keuffel, and a commercial model of this instrument was made and sold by the Keuffel and Esser Company. About the same time an eyepiece for the observation of spinning disks in comparison with a sample such as cotton or hay was developed for work in the Department of Agriculture laboratories by the. In 1933 this was followed by the manufacture of a simplified form of disk colorimeter, the Bausch and Lomb HSB Color Analyzer—HSB for 1922 Optical Society terms hue, saturation, and brilliance. When this instrument appeared, the Keuffel and Esser Company stopped making the larger type. A revised model of the Bausch and Lomb disk colorimeter is now completed, and it is hoped that the rush of optical work due to the present defense program will not unduly delay its commercial production.

In 1929 the disk method of color measurement, using Munsell disks as secondary standards, was described in a technical bulletin of the U. S. Department of Agriculture. Since that time, the method of disk colorimetry, using disks calibrated for measurement of particular products, has spread to many fields of work, sometimes with instruments, sometimes without. Three papers by the writer concerning this method have appeared in the Journal of the Optical Society, , and other reports concerned with disk colorimetry have been published elsewhere. A technical paper to serve as a handbook on disk colorimetry is now in preparation by the Department of Agriculture.

Other developments outside of the Munsell laboratories consist chiefly of the 1935 Glenn Killian data on the Munsell papers ; the work of a subcommittee of the Colorimetry Committee of this society in reviewing the spacing of the Munsell system ; measurements by Granville, Nickerson, and Foss of the more than 400 special Munsell papers (in addition to those which appear on the regular charts) ; a report by Tyler and Hardy at the October, 1939, O.S.A. meeting ; a report by Nickerson and Granville in the April, 1940, Journal of the Optical Society ; preparation of I.C.I. values for the