Memoir of Dr. Thomas Young. 249 



Sauvages, Bourdelot, consider also, that a varia- 

 tion in the curvature occurs, but only in the crystalline lens. 



Such is also the system of Young. Two memoirs pre- 

 sented successively to the Royal Society contain its com- 

 plete development. 



In the first, the question is only viewed in an anatomical 

 light. Young demonstrated, by means of direct and very 

 delicate observations, that the crystalline lens is possessed 

 of a fibrous or muscular structure, admirably adapted to 

 all kinds of changes in form. This discovery overturned 

 the only solid objection which had hitherto been opposed 

 to the hypotheses of Sauvages, Bourdelot, &c. Scarcely 

 was it published when Hunter claimed it. The celebrated 

 anatomist thus assisted the interest of the young beginner, 

 since his work, unpublished, had been communicated to 

 no one. However, this part of the discussion soon lost all 

 its importance, for it was shewn that Leeuwenhoek, sup- 

 plied with powerful microscopes, had already traced and 

 designed the muscular fibres of the crytsalline lens of a 

 fish in all their ramifications. To awaken the public at- 

 tention, fatigued with so many debates, nothing less would 

 have satisfied than the high renown of two new members 

 of the Royal Society who entered the lists. One of these 

 an expert anatomist, the other the most celebrated artist 

 of which England could then boast, presented to the Royal 

 Society a memoir, the fruit:, of their combined efforts, and 

 destined to establish the completely unalterable nature of the 

 crystalline lens. The philosophical world, with the greatest 

 hesitation, would have admitted, that Sir Everard Home and 

 Ramsden together could have made inaccurate experiments; 

 that they could have been deceived in the micrometical 

 measurements. Young himself did not believe it ; and im- 

 mediately in a public manner renounced his theory. This 

 eagerness to confess that he was overcome, so rare in a 

 young man of twenty-five years, so rare especially in the 

 case of a first publication, was here an act of unexampled 

 modesty. Young, in fact, had nothing to retract. 



In 1800, having withdrawn his disavowal, he developed 

 anew the theory of the change in form of the crystalline 

 lens in a memoir, to which no serious objection has been 

 since made. Nothing can be more simple than his line of 

 argument, nothing more ingenious than his experiments. 



