128 Captain Rozet on the Surface of the Moon. 



which they are traversed, so is the degree of metamorphism 

 increased. He insists much on the metamorphic action of 

 quartz veins, which he holds to be of eruptive nature ; refers 

 to the growing conviction among geologists, that, in many 

 cases, there have been eruptions of veins of calcareous spar ; 

 and even ascribes the veins and slender ramifications of gyp- 

 sum, in the argillaceous beds of the lias of Burgundy and the 

 other eastern provinces of France, to eruptions of sulphate of 

 lime. 



(To he concluded in next Number.) 



On the Surface of the Moon. By Captain Rozet. 



M. Elie de Beaumont has already been enabled, by means 

 of the beautiful selenographic delineations of Lohrnaann, and 

 of Beer and Madler, to make some very remarkable compa- 

 risons between the forms presented by certain portions of the 

 mountainous masses of the earth, and the annular openings 

 of the surface of our satellite. 



During the summer of 1844, one of my friends having di- 

 rected my attention to the circular forms of nearly the whole 

 of the variations of the lunar surface, I have devoted myself 

 since that time to the study of the phenomena presented by 

 these variations of surface, having, at the same time, called 

 in the aid of the beautiful German maps, and of various works 

 already published on the subject. 



The contours of all the great greyish spaces which, for a 

 very long time, have been termed Seas^ although it is known 

 with certainty that they cannot be masses of water, are 

 formed by arcs of circles which intersect one another. The 

 number of arcs sometimes amounts to two, rarely to one 

 mare crisium. These contours present circular escarpments 

 which seem perpendicular, but the inclination of many of 

 which is 45 degrees. The matter composing them appears to 

 be swelled up, and their height often exceeds 4000 metres 

 (upwards of 13,000 English feet). In the interior of the seas 

 we remark annular openings or perfect rings, whose diame- 

 ter amounts to 10 myriametres (upwards of 60 Ei^lish miles), 

 and the height of whose terminal ridge is 4000 metres. Seve- 



