342 COSMOS. 



extended pumice quarries, four miles and a half from Lao 

 tacunga, present, according to my investigation of the local 

 conditions, an analogy with this occurrence on Lipari. These 

 quarries, in which the pumice-stone, divided into horizontal 

 beds, has exactly the appearance of a rock in position, ex- 

 cited even the astonishment of Bouguer in 1737 32 . "On vol- 

 canic mountains," he says, " we only find simple fragments 

 of pumice-stone of a certain size ; but at seven leagues to 

 the south of Cotopaxi; in a point which corresponds with 

 our tenth triangle, pumice-stone forms entire rocks, ranged in 

 parallel banks of 5 to 6 feet in thickness in a space of more 

 than a square league. Its depth is not known. Imagine 

 what a heat it must have required to fuse this enormous 

 mass, and in the very spot where it now occurs ; for it is 

 easily seen that it has not been deranged, and that it has 

 cooled in the place where it was liquefied. The inhabitants 

 of the neighbourhood have profited by this immense quarry, 

 for the small town of Lactacunga, with some very pretty 

 buildings, has been entirely constructed of pumice-stone, since 

 the earthquake which overturned it in 1698." 



The pumice quarries are situated near the Indian vil- 

 lage of San Felipe, in the hills of Guapulo and Zumbalica, 

 which are elevated 512 feet above the plateau and 9990 feet 

 above the sea level. The uppermost layers of pumice-stone 

 are, therefore, five or six hundred feet below the level of 

 Mulalo, the once beautiful villa of the Marquis of Maenza 

 (at the foot of Cotopaxi), also constructed of blocks of 

 pumice-stone, but now completely destroyed by frequent 

 earthquakes. The subterranean quarries are at unequal 

 distances from the two active volcanoes, Tungurahua and 

 32 Bouguer, Figure de la Terre, p. Ixviii. How often, since the earth- 

 quake of the 19th July, 1698, has the little town of Lactacunga been 

 destroyed and rebuilt with blocks of pumice-stone from the subterra- 

 nean quarries of Zumbalica ! According to historical documents com- 

 municated to me during my sojourn in the country, from copies of the 

 old ones which have been destroyed, and from more recent original 

 documents partially preserved in the archives of the town, the destruc- 

 tions occurred in the years 1703 and 1736, on tho 9th December, 

 1742, 30th November, 1744, 22nd February, 1757, 10th February, 

 1766, and 4th April, 1768, therefore seven times in 65 years! In 

 the year 1802 I found four-fifths of the town still in ruins in conse- 

 quence of the great earthquake of Riobamba on the 4th February, 

 1797. 



