90 



SCIENCE. 



[Vol. I., No. 4. 



We have reports, also, from time to time, 

 of a sj'stem of experiments and observations 

 made bj' M. Fa3'ol, at Commentry, in the 

 department D'Alliers, in Central France, from 

 which he draws the same inference ; and it is 

 apparent that a formidable attack has been 

 made all along the line upon the peat-bog 

 theorj'. 



For this reason, and in .order that geological 

 truth shall be maintained, I venture to report 

 some facts which I have mj'self observed 

 in the coal-fields of the Mississippi vallej', 

 and which in my judgment are incompatible 

 with the conclusions of MM. Grand'Eury 

 and Fajol. 



The opinions presented in the discussions of 

 the chemical and phj'sical histoiy of coal have 

 been based upon two classes of facts : viz., 1°, 

 those gathered from the study in the field of 

 the structure and relations of the coal-beds ; 

 and, 2°, those obtained from chemical and 

 physical experiments conducted in the labora- 

 tory. Now, while there is no doubt that such 

 experiments have contributed much to our 

 understanding of the subject, it is obvious 

 that the^- have misled observers, through the 

 impossibilitj' of imitating hy artificial means 

 the grand processes of nature. She has in 

 most instances left a full and faithful record 

 of her work ; but the same difficulties attend 

 the disinterment and translation of this buried 

 record that have been encountered by the stu- 

 dents of archeology in their efibrts to trace 

 the earlj' history of mankind. Necessarilj^ 

 this is a work of time ; and much study is re- 

 quired for the acquisition of a full and accurate 

 knowledge of the language in which it is 

 written, and for the gradual accumulation of 

 the large amount of material required. Yet I 

 claim, that so much of nature's record of the 

 processes pursued in the formation of coal has 

 been submitted to our observation, and that 

 this record is so clear that the truth is within 

 our reach ; and, further, that this truth is dis- 

 cordant with the results obtained in artificial 

 experimentation, and therefore proves such 

 results fallacious. 



In the present communication, nothing like 

 a full discussion of the arguments pro and 

 con will be attempted ; sijice the space at mj- 

 command will permit me to cite only a few of 

 many facts, and to very brieflj' read their 

 meaning. 



For the present I will confine myself to 

 some of the phenomena presented hy one of 

 the Ohio coal-beds with which I am specially' 

 familiar. This is our ' Coal No. 1,' the lowest 

 of the series, sometimes called the Brier-Hill 



coal. As this has furnished a fuel of excep- 

 tional purity, such as could be used in the raw 

 state for the smelting of iron, and lies nearer 

 to the navigable waters of Lake Erie than any 

 other, it has been very extensively worked. 

 The result of this working has been to show, 

 that the coal is confined to a small part of the 

 area it was once supposed to cover, and that 

 it lies in a series of narrow troughs, or basins, 

 which were evidentlj' once peat-marshes, oc- 

 cupj'ing local depressions in the then existing 

 surface. A large number of these detached 

 coal-deposits have been now completely worked 

 out, and the phenomena they present fully 

 exposed to view. Among these phenomena I 

 maj' cite : — 



1. Below the coal a fire-claj^, penetrated in 

 everj' direction wit& roots and rootlets of Lepi- 

 dodendron, Sigillaria, etc. 



2. A coal-seam having a maximum thick- 

 ness of six feet in the bottom of the basins, 

 thinning out to feather-edges on the sides, 

 and containing onlj' two to three per cent of 

 ash. 



3. The coal on the margins of a basin ris- 

 ing sometimes thirty or fort}' feet above its 

 place on the bottom. 



4. A roof composed of argillaceous shale, 

 of which the lower layers, a few inches in 

 thickness, are crowded with the impressions 

 of plants ; among which are interlocked pros- 

 trate trunks of Lepidodendra and Sigillaria, 

 traceable from root to summit, often carrying 

 foliage and fruit, the fronds of ferns, — some- . 

 times ten or fifteen feet in length, complete 

 and smoothly sjDread, — Calamites, Cordaites, 

 etc. 



5. In manj' places the roof marked with 

 circles one to two feet in diameter, called by 

 the miners ' pot-bottoms.' These are sections 

 of the bases of the upright trunks of Sigillaria 

 or Lepidodendron, which rise perpendicularly., 

 sometimes many feet, into the overlying shales. 

 They consist of hollow cylinders of coal, per- 

 haps a half-inch in thickness, the interiors of 

 which are filled in with shale, laminated hori- 

 zontally', and sometimes contain remains of 

 plants and animals which must have been intro- 

 duced when they were hollow stumps standing 

 where thej' grew. 



6. In certain circumscribed areas, part of 

 the coal-seam is cannel, bituminous shale, or 

 black-band iron-ore ; and, as in all cases of 

 this kind, the cannel, shale, and black-band 

 contain the remains of aquatic animals, — Crus- 

 tacea, fishes, or mollusks, — the normal or cubi- 

 cal coal never including anj' thing of the kind. 



7. The boundaries and bottoms of the chan- 



