406 Mr. Smith on the Stream Work of Pentowan. 



The lower Pentowan work lies three quarters of a mile south of 

 the upper, and about half a mile north of the sea. The plain is 

 more contracted here than at the upper work, and the river flows 

 immediately west of the excavation, and nearly on a level with the 

 upper part of it. The excavation measures from north to south 

 about 400 feet, from east to west about 250, and is 54|- feet deep. 

 In form it resembles an amphitheatre, being cut into deep stopes 

 (as the miners term them) by which their work is upheld. The 

 miner's object is to come at a deposit of tin five feet thick at the 

 bottom of the pit, and as he works forward he throws behind 

 him the waste matter. Water is conveyed from the river by a 

 wooden trough into an insulated mass of the lower stratum, in 

 which the tin is washed. 



The following is the Section of the Strata at the Lower Work. 



Depth from 

 surface 

 Feet. Inches 



Stratum 1. Soil with trees growing in great luxuriance, some very old, 



and gravel towards the bottom 3 3 



2. Fine peat. At the bottom are roots of trees, fallen trunks 



with ivy attached to them, and sticks impregnated with 

 salt. In this stratum also are found sea laver and 

 rushes 12 15 



3. Sea mud, which when dry resembles fine grey sand. At 



the top are masses of leaves compressed flat, whose 

 characters are still to be distinguished. Under the leaves 

 are cockle shells, well preserved. These as the stratum 

 deepens become more decayed. At 4 feet from the 

 bottom of this stratum, and at 31 feet from the surface 

 hate been found many bones of animals, viz. the horns 

 of two deer, very large and of equal size; two human 

 skulls, one belonging to a child, the grinders not having 

 yet shot through the jaw; the shoulder and thigh bone 

 of some large animal; and the vertebrae of some smaller 

 animals. At the bottom is a bed of very small shells 

 in great abundance, 1 foot thick, and then a thin layer 

 of small shells in a very decayed state 2© 35 



