522 Additional Notes, 



ginal structure of our globe; that it proves that mountains 

 are not mere fortuitous eruptions, as some, within a few years 

 past, have confidently advanced ; and that it furnishes a power- 

 ful argument in favour of the Mosaic account of the creation, 

 dekige, &c. — S^QTransactions of the Royal Irish Academi/, 

 vol. vii. 



Meteorology. 



Weight of the Atmosphere, p. 1 90. 



The eighteenth century is distinguished by the numerous 

 and enlightened experiments which were made during this 

 period to ascertain the weight of the atmosphere in ditferent 

 latitudes and situations. For these we are principally indebted 

 to M. BouGUER, M. Cassan, and M. Cotte, of France; 

 and to Sir George Shuckburgh, Lord Mulgrave, and 

 Mr. Kir WAN, of Great-Britain and Ireland. 



Purity of the Atmosphere, p. 190. 



Though the experiments on the Eudiometer were men- 

 tioned under the head of Chemistry, and in some respects 

 belong to that department of science, yet they also belong to 

 Meteorology, and have contributed to throw some light on 

 this obscure subject. These experiments, and the inquiries 

 connected with them, belong exclusively to the eighteenth 

 century. 



Atmospherical Electricity, p. 1 92. 



All our knowledge of Atmospherical Electricity is the 

 product of the eighteenth century. To this subject the at- 

 tention of philosophers has been particularly drawn since the 

 time of Dr. Franklin's discovery that lightning and thunder 

 are occasioned by the agency of Electricity. 



*' The most complete set of experiments on rliis part of 

 meteorology were made by Professor Beccarta, of Turin. 

 He found that the air is almost always positively electrical, 

 especially in the day-time, and in dry weather; that when 

 dark or wet weather clears up, the electricity is always nega- 

 tive; and that low thick fogs, rising into dry air, carry up a 

 great deal of electric matter. He ascertained that the mid- 



