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LECTURE LX. 



ON THE HISTORY OF TERRESTRIAL PHYSICS. 



THROUGHOUT the whole of nature, we discover a tendency to the mul- 

 tiplication of life, of activity, and of enjoyment : man is placed at the head 

 of terrestrial beings, the only one that comprehends, and that can trace, in 

 a faint outline, the whole plan of the universe. We have seen the innumer- 

 able luminaries which enliven the widely expanded regions of immeasur- 

 able space, with their brilliant, but distant emanations of light and heat. 

 Revolving round them at lesser intervals, and cherished by their fostering 

 influences, are their planets and their comets ; those preserving their dis- 

 tances nearly equal, and these, ranging more widely from the upper to the 

 lower regions, without limits to their numbers or to their motions. Having 

 conjectured what might possibly exist on other planetary globes, we 

 descended to our own, and examined its structure and the proportions of 

 its parts. Next we studied the general properties of the matter within our 

 reach, and then the particular substances or qualities that are either 

 not material, or are distinguished by very remarkable properties from 

 other matter, as we found them concerned in the phenomena of heat, of 

 electricity, and of magnetism ; and we afterwards examined the combi- 

 nations of all these, in the great atmospherical apparatus of nature, which 

 serves for the exhibition of meteorological phenomena. The forms and the 

 laws of animal and vegetable life have been the last objects of our inqui- 

 ries ; but the magnitude of some departments of natural history, and the 

 obscurity of others, have prevented our entering more than superficially 

 upon any of them. 



Of the gradual advancement of astronomy we have already taken a his- 

 torical view. With respect to the other sciences comprehended under the 

 denomination of proper physics, the progress of discovery has generally 

 been slow, and frequently casual. The ancients had little or no substantial 

 knowledge of any part of physics, except astronomy and natural history : 

 their opinions were in general mere speculations, derived from fancy, and 

 inapplicable to the real phenomena of nature. Opinions such as these will 

 only require to be so far examined, as to enable us to trace the imperfect 

 rudiments of discoveries, which were only completed after intervals of many 

 ages. 



The Chinese are said to have been acquainted with the use of the com- 

 pass above 3000 years ago ; but in such accounts, it is impossible to ascer- 

 tain how far the spirit of national vanity may have induced a historian to 

 falsify his dates.* It has been conjectured that the death of Numa, like 

 that of Professor Richmann, was occasioned by some unguarded experi- 

 ments on the electricity of the atmosphere, which drew on him the, effects 



* Consult Davies on the History of Magnetical Discovery, British Annual, 1837. 

 Klaproth, Lettre a M. de Humboldt sur 1' Invention de la Boussole. 



