IN THE CONTEMPLATION OP THE UNIVERSE. 855 



operation of the Indian maritime commerce, and of the 

 Alexandrian Institute under the Lagidse ; by the Roman 

 Universal Empire under the Csesars ; and by the epoch of 

 the Arabians, from whose attachment to the study of nature 

 and of her powers, and especially to astronomical and 

 mathematical knowledge, and to practical chemistry, great 

 benefits were derived. The series of external events which 

 suddenly enlarged the intellectual horizon, stimulating men 

 to the research of physical laws, and animating them to the 

 endeavour to rise to the ultimate apprehension of the 

 Universe as a Whole, closed, according to my view, with 

 those geographical discoveries, the greatest ever achieved, 

 which placed the nations of the Old Continent in possession 

 of an entire terrestrial hemisphere till then concealed. From 

 thenceforward, as we have already remarked, the human 

 intellect produces great results, no longer from the incite- 

 ment of external events, but through the operation of its 

 own internal power ; and this simultaneously in all directions. 

 Nevertheless, amongst the instruments which men formed 

 for themselves, constituting as it were new organs augment- 

 ing their powers of sensuous perception, there was one 

 which acted like a great and sudden event. By the space- 

 penetrating power of the telescope, a considerable portion of 

 the heavens was explored as it were at once ; the number of 

 known celestial bodies was increased, and their form and 

 orbits began to be determined. Mankind now first entered 

 on the possession of the " celestial sphere" of the Cosmos. 

 It appeared possible to found a seventh section of the history 

 of the physical contemplation of the Universe, on the 

 importance of these occurrences, and on the unity of the 



