Proceedings of the British Association. 215 



knowledge, in the preparation for mounting the great telescope of 

 six feet diameter and fifty- four feet focal length, yet much remained 

 to be done : but I am quite sure that the members of the Association 

 will learn with unmixed satisfaction, that the noble Lord has entirely 

 succeeded in his great undertaking — that the great telescope has al- 

 ready made its essay, and that its performance is in every way satis- 

 factory, and that he proposes to communicate to the Mathematical 

 and Physical Section in the course of the present meeting, an account 

 of the process which he has followed in the preparation and polish- 

 ing of his mirrors, and of the expedients which he has adopted for 

 bringing under the most perfect control the movement of the vast 

 masses with which he has had to deal. 



It is now more than sixty years since the elder Herschel, by the 

 superior optical and space-penetrating powers of his telescope, began 

 a brilliant career of astronomical discovery ; and the interest which 

 the construction of his great forty-foot reflector, a memorable monu- 

 ment of his perseverance, genius and skill, excited amongst men of 

 science of that period, was not, if possible, less intense than what 

 now attaches to the similar enterprise of the noble Lord : nor were 

 the expectations which were thus raised disappointed by the result ; 

 for though this noble instrument was generally reserved for the great 

 and state occasions of astronomy only, requiring too great an expen- 

 diture of time and labour to be producible for the daily business of 

 observation, yet the very first time it was directed to the heavens it 

 discovered the 7 th satellite of Saturn, and contributed in no inconsi- 

 derable degree to the more complete development of those views of 

 the construction of the heavens (I use his own expression) which his 

 cotemporaries never sufficiently appreciated, but which present and 

 future ages will probably regard as the most durable monument of 

 his fame. It is no derogation to the claims of this great discoverer 

 that art and knowledge are progressive, or that a successor should 

 have arisen, who, following in the track which he has pointed out, 

 should bring a considerable zeal and more ample means to prepare 

 the way for another great epoch in the history of astronomical dis- 

 covery ; and I know that I do not misstate the sentiments of the ac- 

 complished philosopher who has succeeded to his name and honours, 

 and who throughout his life has laboured with such exemplary filial 



