Thomas Young is regarded as one of the most versatile of all scientists. In the above work he showed that the act of accommodation is due to a change of curvature of the crystalline lens, whereby light rays of various lengths can be brought to a focus on the retina.

Young's thesis for his medical degree from Göttingen on the conservation of strength in the human body, which also contains, on the final four pages, the only extant fragment of Young's brief thesis on the human voice prepared for his oral examination. It was this last, as Young's biographer tells us, that began Young on his career in physics: "[The fragment] gives an alphabet of forty-seven letters designed to express, by their combination, every sound which the organs of the human voice are capable of forming. . . . Here we see his early and sustained interest in languages combined with his interest in anatomy. From this combination he developed an interest in the production and propagation of sound...." (Wood / Oldham, Thomas Young, pp. 49-50). Digital facsimile from wellcomecollection.org at this link.

Includes the first description of astigmatism, with measurements and optical constants.

Young, the “Father of physiological optics”, established the wave theory of light, explaining the phenomena of interference and dispersion.

The remarkable Thomas Young compiled this bibliography of works which he considered necessary to a complete medical library. Second edition, 1823.