189 



TAB. CC. 



FERRUM sulphureum. 

 Iron Pyrites in petrified Wood. 



1 he upper specimen seems to have been part of a cylin- 

 drical piece of wood, and was found 260 feet below the sur- 

 face of the earth in digging a well in Richmond Park in 

 1804. It appears to have had worm-holes, or holes of 

 Terebellce, perforating it in various directions, which may- 

 be presumed to have happened before the process called 

 petrifying had taken place. This may more properly be 

 called Pyritaceous Wood, as the Pyrites or Sulphuret of 

 Iron has filled the pores of the wood so perfectly, that the 

 shape, and somewhat of the texture of wood, was seen, 

 but as if formed of Pyrites. The worm-holes, some lined 

 with Pyrites, and others doubly lined. One side being 

 nearly covered with Pyrites makes it a beautiful specimen, 

 as well as an instructive one. The lower piece was per- 

 haps of different wood, appearing like part of a plank. 

 This was found 100 feet deep in digging a well for Mr. 

 Truman's brewhouse, Spitalfields, London. The worm- 

 holes are lined like the other ; but they seem to hive been 

 a particular species which prefer a straight direction, cross- 

 ing the fibres of the wood. It is somewhat remarkable 

 that the woody nature remains, and being found damp and 



