THE MICROSCOPY OF ANTHRACITE COAL 



3" 



the large lumps of char- 

 coal examined have the 

 structure of com'fer wood. 

 Rings of growth, medullary- 

 rays, and bordered pits are 

 distinctly shown. 



Ordinary commercial 

 charcoal differs from the 

 mineral charcoal in no es- 

 sential detail when exam- 

 ined with the microscope. 

 This condition seems to 

 argue against regarding the 

 charcoal as the product of 

 forest fires, for it seems pro- 

 bable that the cells would 

 either have been filled with 

 the putrefaction product 

 solutions during subsequent 

 immersion in the bog, or 

 crushed under the pressure of over- 

 lying material. 



The brilliant layers of the coals 

 examined show, under the micro- 

 scope, either no structure or a 

 preponderance of wood fiber and 

 wood cells. In the glossy duller 

 layers are found spore exines, former 

 resinous materials, apparent vas- 

 cular bundles, cuticles, wood fiber, 

 cell laminae, and other forms not 

 yet identified. The thin dull black 

 layers usually show wood fiber and 

 wood cells either well pieserved or 

 crushed to an almost structureless 

 mass. Further microscopic details 

 can be most advantageously de- 

 scribed in the legends of the micro- 

 photography. 



Fig. 4. — Section ( X 50) parallel to the bedding 

 of the Forge split of the Mammoth bed from 

 Nanticoke, Pennsylvania. A section of wood 

 showing original cell laminae. The remarkable 

 preservation of these cells may be due in part to 

 the silicious filling shown by the gray areas within 

 the cell walls, although some of the cells are filled 

 witli black, lusterless carbonaceous material. 



Fig. 5. — Section (X126) crosswise 

 to the bedding and oblique to an appar- 

 ent stem in anthracite from Pennsyl- 

 vania. This section is of particular 

 interest because it is in the brilliant 

 jetty coal and not in the duller layers 

 where such forms are usually found. 



