40 RAMBLES AND REVERIES. 



studying this is at the works of the West of England 

 China Clay Company at Nanpean, near St. Austell. 

 It was here that the party of which I was a member 

 had the opportunity of observing all the processes 

 through which the natural product has to go, from 

 its extraction out of the earth to its final washing 

 and baking that fit it for the potter. 



Every one knows that there are enormous quan- 

 tities of granite in Cornwall. Granite used to be 

 regarded as the basic or foundation rock of the 

 earth's strata, but it is now known to have burst 

 its fiery way through various strata during almost 

 every geological period, and it was the upheavals 

 or eruptions of the molten masses which afterwards 

 cooled in the form of granite that transformed the 

 barren schists of Cornwall into rocks that are veined 

 with metalliferous lodes. Geologists are of opinion 

 that the series of extensive granite bosses which 

 stretch from Dartmoor to the Scilly Islands first 

 appeared after the deposition of the Upper Devonian 

 rocks. In fact, the leading feature of Cornish 

 geology now may be described as a group of granite 

 islands protruding out of a sea of Devonian schists. 

 The composition of granite, though varying in 

 difierent districts in regard to minor characteristics, 

 is mainly a mixture of quartz, mica, and felspar. 

 In some kinds the grains are very small, while in 

 others huge quartz crystals are seen an inch or 

 more in length. About half the bulk of granite is 

 made up of felspar, which is in reality hardened 

 volcanic lava. Cornish felspar is a silicate of 

 alumina and potash. 



