1S8 Scientific Intelligence. — Geology, 



as brightly as during the beautiful evenings of France or Switzerland, 

 It is the same in the other Hebrides, in the Orkneys, Shetland, the 

 whole of the western coast of the north of Scotland, and in the high 

 regions of the Highlands. Now, it is to be remarked, that in none of 

 these places are there any large towns, scarcely even burghs or large 

 villages, and no manufactories of large extent which burn coal ; the 

 thinly -scattered population of these solitary regions use no other fuel 

 but turf or wood, the very light smoke of which is soon dissipated 

 without obscuring the atmosphere. Therefore, the sky is as pure as 

 in any part of continental Europe. In the lower part of Scotland, on 

 the contrary, and along the eastern and north-eastern side of the 

 country, where towns, large villages, and manufactories abound, and 

 Avhere coal is the ordinary fuel, not only the towns and their immediate 

 environs have their atmosphere obscured by a dense smoke, which the 

 wind drives from one side or another, but even in' the country most 

 remote from towns we may perceive that the air is still very foggy at 

 all seasons from this coal-smoke. It is the same with England, and 

 even when sailing, as I have pretty frequently done, along the pa»t of 

 the German Ocean which washes the eastern side of the British islands, 

 I have been always struck by the want of clearness in the air and its 

 misty appearance. Nothing could shew to me more clearly that this 

 fact was owing to the coal-smoke, than to see from the island of Ar- 

 ran, and especially from the tops of its mountains, during the finest 

 months of spring and beginning of the summer of 1839 (while Arran 

 itself was enjoying the purest air and sky), the opposite coasts of Ayr 

 and Renfrew constantly overhung by a belt of thick fog, like a long 

 grey cloud, rising to 1 or 1 J degrees on the horizon. It is not, then, 

 sui^prising that the scintillation of the stars should be affected by it. 

 But what influence can the aurora borealis have in re-establishing the 

 scintillation ? Of this I am ignorant.*'' 



GEOLOGY. 



Surface of the Terrestrial Globe. — M. Rozet lately read a memoir to 

 the Philomathic Society of Paris, on some of the irregularities presented 

 by the structure of the terrestrial globe. 



For twenty-five years the royal corps of geographical engineers, 

 blended in 1831 with that of the FMt Major, has been engaged in exe- 

 cuting a great topographical map of France. The numerous geodesical 



* From Comptes Rendus, t. xii. No. 7, 15 Fev. 1841, p. 317- 



