if you want to see more of their work, i highly suggest the following book:
W. B. Ferguson, The Photographic Researches of Ferdinand Hurter & Vero C. Drieffield, Morgan & Morgan, Facsimile Edition, 1974
In the first half of the 20th century further valuable in-depth photographic research was conducted. Among others, Loyd A. Jones and his colleagues at the research laboratories of the Eastman Kodak Company in Rochester, New York deserve major credit and respect for their contribution. He and his team published several historic papers of which a few are most important to this book. Despite its age, this research is largely up-to-date and still a milestone in the evolution of photographic science. Contact your local library to obtain copies of these most valuable papers.
Loyd A. Jones, ‘The Evolution of Negative Film Speeds in Terms of Print Quality’, Journal of the Franklin Institute, Mar/1939, Page 297 - 354
Loyd A. Jones and C. N. Nelson, ‘A Study of Various Sensitometric Criteria of Negative Film Speeds’, Journal of the Optical Society of America, Mar/1940, Page 93 - 109
Loyd A. Jones and H. R. Condit, ‘The Brightness Scale of Exterior Scenes and the Computation of Correct Photographic Exposure’, Journal of the Optical Society of America, Nov/1941, Page 651 - 678
Loyd A. Jones and C. N. Nelson, ‘The Control of Photographic Printing by Measured Characteristics of the Negative’, Journal of the Optical Society of America, Aug/1942, Page 558 - 619
Loyd A. Jones and C. N. Nelson, ‘Control of Photographic Printing: Improvement in Terminology and Further Analysis of Results’, Journal of the Optical Society of America, Nov/1948, Page 897 - 920