110 Horner's Geological Address. 



sections above examined, we have eighty-four seams oiF coal in 

 the one, and seventy-six in the other. In the Saarbriick coal- 

 field there are 120 seams, without taking into account the 

 thinner seams, those less than a foot thick.* The materials 

 of each of these seams, however thin (and there are some not 

 an inch thick, lying upon and covered by great depths of 

 sandstones and shales), must, according to this theory, have 

 grown on land, and the covering of each must have been de- 

 posited under water. There must thus have been an equal 

 number of successive upward and downward movements, and 

 these so gentle, such soft heavings, as not to break the con- 

 tinuity or disturb the parallelism of horizontal lines spread over 

 hundreds of square miles ; and the movements must, more- 

 over, have been so nicely adjusted, that they should always 

 be downward when a layer of vegetable matter was to be 

 covered up ; and in the upward movements, the motion must 

 always have ceased so soon as the last layers of sand or 

 shale had reached the surface, to be immediately covered by 

 the fresh vegetable growth ; for, otherwise, we should have 

 found evidence, in the series of successive deposits, of some 

 being furrowed, broken up, or covered with pebbles or other 

 detrital matter, of land long exposed to the waves breaking 

 on a shore, and to meteoric agencies. These conditions, which 

 seem to be inseparable from the theory in question, it would 

 be difficult to find any thing analogous to in any other case 

 of changes in the relative level of sea and land with which 

 we are acquainted. 



That some seams of coal were formed of vegetable matter 

 that grew on the spot where the coal now exists, seems to be 

 proved in several cases (such, for instance, as that of the 

 Bolton railway section) beyond dispute ; and that some seams 

 afford proofs of having been formed by drifted vegetable mat- 

 ter may be true. The coal-seams, and the beds associated 

 with them, could be formed in no other way than under water ; 

 and the accumulation of the vegetable matter near the surface 

 of it, and a very gradual submergence of the land, arrested 

 at unequal intervals, appear to be the conditions most recon- 

 cileable with the phenomena. This implies, however, a de- 



* Humboldt's Kosmos, p. 295. 



