Professor Secchi's Description of Lunar Volcanoes. 161 



its exploration was a most important desideratum in a com- 

 mercial and geographical point of view. If the searching 

 operations are to be based on a comprehensive and exhaus- 

 tive system, my scheme cannot possibly be left unconsidered 

 and neglected. The commercial interests of the country 

 likewise demand an early exploration of the region to which 

 I have drawn attention, and science looks eagerly forward 

 to the solution of one of the most interesting of geographical 

 problems. Moreover, when it is considered that five years' 

 increasing efforts from one side have hitherto proved com- 

 plete failures, the other side, so promising as regards an 

 easy and speedy access with the aid of steam, should no 

 longer be neglected. As yet the missing voyagers may not 

 all have perished, but a further delay of one or two years 

 may not leave one of them to tell the woeful tale of their 

 sufferings, and may repeat the fearful case of Sir Hugh 

 Willoughby 1 s Expedition, where the stiff and frozen corpses 

 only were found on the dreary shores of the Arctic regions. 



A Description of Lunar Volcanoes. By Professor Secchi. 



Professor Secchi divides the Lunar Volcanic Formations 

 into three classes, and he says, " a fourth may be added, 

 analogous to our Plutonian Formations. 



" The first class of the lunar volcanoes possesses a dis- 

 tinctive character ; that the edges of the craters are almost 

 completely obliterated, so that their border now is a conti- 

 nuation of the plane ground, in which they seem excavated, 

 and a deep well only remains in the place of the ancient 

 mouth of the volcano. Instances of this kind are very fre- 

 quent near the south pole of the moon, and around the large 

 spot Tycho; but Tycho itself does not belong to this class. The 

 physiognomy of these craters nearly resembles our submarine 

 volcanoes of the Monti Ciminii to the north-west of Rome. 

 The country around the craters of Braceiano, Bolsena di 

 Vico, is almost flat, and the old openings of the craters are 

 now deep lakes. On this ground we are led to believe that 

 even in the moon many subaqueous volcanoes existed. 



VOL. LV. NO. CIX. — JULY 1853. L 



