WkeeJing Coal Strata,. SI 



3. Greenish colored, siliceous rock, breaking into parallelograms 

 or cubes, from one to four inches in thickness. Its composition is 

 much like the common honestone and answers for the same pur- 

 poses. — 6 feet. 



4. Yellowish, argillaceous deposit, interspersed with nodules of 

 limestone- — 14. 



5. Fine grained, argillaceous sandstone, in thin strata, with fine 

 plates of mica, in horizontal seams ; color, dajk brown or grey. It 

 makes good grindstones : lower part of the bed carbonaceous, resting 

 on coal. — 12 feet. 



6. Coal deposit; slaty and poor; bed not W'orked. — 2 feet. 



7. Limestone rock ; thick deposit of nearly twenty four feet, in dis- 

 tinct beds, deposited at different periods and with different chemical 

 affinities. The upper part of the bed five feet in thickness, is a dark 

 carbonaceous rock, lying under the coal. The succeeding bed is of 

 a light dove color, fine grained, and contains much argillaceous mat- 

 ter combined with the calcareous.. Thin, fine, ash colored veins 

 pass through It in all directions, but generally horizontally ; on expo- 

 sure to frosts and rain it decomposes into a fine rich marl. This 

 stratum is six feet in thickness. The next five feet is ash colored ; 

 more compact ; and when burnt makes a strong lime m.ortar ; it con- 

 tains some faint indications of fossil shells. The bottom stratum is 

 eight feet in thickness — a dark, compact, carbonaceous rock. It is 

 considerably charged with iron — the surface being covered with 

 rust or brown oxide, when exposed to the air; reposing on the coal 

 bed below\ — 24 feet. 



8. Bituminous coal; slaty structure; fracture glistening; does 

 not burn freely. In mining, or digging out the coal from the deposit 

 below, this bed is left for a roof to the mine. — 2 feet. 



9. Dark, carbonaceous, slate clay, filled with the impressions of 

 various species of calamites, and the thick leaves oi some aquatic 

 plant, like the Nelumbium luteum. In the operation of mining, 

 this bed is removed with the coal, being too fragile and tender, falling 

 upon the workmen. — 1 foot. 



Main 



feet in thick- 



ness ; structure compact and highly bituminous ; between the lam- 

 inae the remains cf the vegetable structure, usually called fossil or 

 mineral charcoal, are seen In considerable abundance ; it is simply 

 the fibre of the vegetable skeleton, and may be seen in many, prob- 

 ably in most varieties of coal, provided they are split fortunately or 



Vol. XXIX.— No. 1- H 



