Memoir of Dr. Thomas Young. 247 



The Royal Society of London enjoys over all the three 

 kingdoms a high and deserved character. The Philosophical 

 Transactions which it has published for a century and a 

 half, the glorious archives where British genius considers 

 it an honour to deposit its titles to the gratitude of posterity. 

 The desire of seeing their names inserted in lists of con- 

 tributors to this truly national collection, after the names 

 of Newton, Bradley, Priestley and Cavendish, has always 

 been the most active, as it is the most legitimate subject of 

 emulation among the students of the celebrated universities 

 of Cambridge, Oxford, Edinburgh and Dublin. That is the 

 boundary of the ambition of the man of science ; he only 

 aspires to it on account of some capital work, and the first 

 essays of youth are communicated to the public in a mode 

 better fitted to their importance, through the medium of 

 those numerous Reviews which with our neighbours have 

 contributed so much to the progress of human knowledge. 

 Such, consequently, ought not to be the course of Young. 

 At the age of twenty, he addressed a memoir to the Royal 

 Society. The council, composed of all the contemporary 

 men of note, honoured this paper with its vote, and it soon 

 appeared in the Transactions. The subject of it was vision. 

 The problem was nothing less than new. Plato and his 

 disciples four centuries before our era had been occupied 

 with it, but their conceptions could only be cited to justify 

 the celebrated and humbling remark of Cicero : " Nothing 

 can be imagined so absurd which will not be supported by 

 some philosopher." 



After an interval of twenty centuries, it is necessary to 

 proceed from Greece to Italy, when we wish to find in 

 reference to the admirable phenomenon of vision, opinions 

 which deserve to be noticed by the historian. There with- 

 out interdicting, like the philosopher of Egina, their stay, 

 to all those who were not geometricians, prudent experi- 

 menters, followed the only road by which man cau be per- 

 mitted to arrive without a false step at the conquest of things 

 unknown ; there Maurolycus and Porta proclaimed to 

 their contemporaries, that the problem of discovering that 

 which is, presents a sufficient number of difficulties without 

 presuming to discover what ought to be ; there these two 

 celebrated countrymen of Archimedes began to develope 

 the catalogue of the different media of which the eye is 



