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turned by a handle only, care being taken to keep the balls in a proper position, and it 

 would be convenient to have the descent of the barrel regulated by the action of a screw, 

 and capable of being suspended at pleasure." 



We pass over many events in his life, his position as foreign 

 secretary of the Eoyal Society 1802, a post which he retained until 

 his death, secretary to the Board of Longitude (1818), conductor 

 of the Nautical Almanac, adviser to an Insurance Company (consult 

 A formula for expressing the Decrement of Human Life, 1826). Nor 

 must we forget that Young in 1827 was the successor of Volta in 

 the Academie des Sciences at Paris. He died in 1829, set. 56, a 

 victim to an atheromatous condition of the blood-vessels. And we 

 omit mention of many of his discoveries on sound, light, &c. 



In 1808 he became a Fellow of the Royal College of Physicians, 

 Physician to St. George's Hospital 1810. In 1813 he published An 

 Introduction to Medical Literature, which included a Nosology. We 

 pass over his " Eriometer " and his measurement of the size of pus cells 

 and blood corpuscles. About 1815 he directed his attention to 

 Hieroglyphics. " His labours in the field of Egyptian literature are 

 the greatest effort of scholarship and ingenuity of which modern 

 literature can boast." 



I am incapable of doing justice to the work of Young, in its 

 bearing on physiology or medicine, but we may refer to certain 

 subjects of general interest. The mechanism of accommodation of 

 the eye for near and distant objects early attracted his attention, and 

 he thought he had found that this was accomplished owing to the 

 muscularity of the lens, and strangely enough John Hunter claimed 

 priority of this somewhat remarkable theory. Leeuwenhoek with 

 his universal inquisitiveness had seen the fibres of lens but mistaken 

 their nature. It matters little : Young's idea of the change of the 

 form of the lens was right, his muscularity theory wrong. His paper 

 contains an excellent description of the position of the planes in the 

 lens, and the course of the fibres he thought were muscular. Later 

 he saw that the theory of accommodation which involved a change in 

 the curvature of the cornea was untenable. The true theory was not 

 yet. His great discovery of the law of interference evoked the 

 wrath of the Edinburgh Reviewers, especially Brougham. This also 

 we pass over, but their criticisms made Young unhappy. His theory 

 of colour vision remained largely unnoticed until Helmholtz re- 

 discovered it, and now this theory is known as the Young-Helmholtz 

 theory of colour vision. (See Fr. Arago, Biograph, of Distinguished 

 Scientific Men, 1857.) 



Thomas Young, scholar, philosopher, linguist, biographer, 

 Egyptologist, reviewer, and discoverer must be regarded as one of the 

 most highly gifted and enlightened men the age has produced, and we 

 are proud to know that medicine claims him as one of her most 



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