ON COAL. • 135 



perhaps bearing rafts of drift titaber, forces back the sea water, occu- 

 pies the estuary, and makes its deposit of clay and sand, containing 

 fragments of such drift timber; in seasons of low water the ocean 

 returns and makes its deposit^ perhaps of limestone, and so on alter- 

 nately. A coal field is supposed by these theorists to be the position 

 of an ancient estuary ; the limestone strata are the marine deposit, 

 the shale and sandstone the river deposit, and the coal seam the 

 imbedded drift timber brought down by the river from distant forests. 



The objections to this theory are all that has been said in favor of 

 the peat bog theory. The pureness of the coal, the fine preservation 

 of even the tenderest parts of plants, the position of such well pre- 

 served specimens always on the upper surface of a coal seam, the 

 structureless character of the great mass of the coal, and, above all, 

 stumps and trunks of trees still erect, with their roots still fixed in 

 the clay stratum below — all this seems not only unaccountable but 

 impossible on this theory. 



In comparing these two theories it will be seen that the first ex- 

 plains completely the phenomena of an individual coal seam, but 

 signally fails to explain the general phenomena of a coal basin, viz : 

 the alternation of coal seam with marine and fresh water strata ; while, 

 on the other hand, the second explains well this alternation, but fails 

 utterly to explain the phenomena of an individual coal seam. There 

 is, then, real and substantial evidence in favor of each, and equally 

 substantial objections. If this had not been the case one or the other 

 would have been relinquished ere this. But we find, on the contrary, 

 that they have both found strenuous advocates from the time geology 

 commenced to exist as a science until now. In every such case of 

 vitality in rival theories it will be found, I think, that there is a real 

 germ of truth in both — that both are true and both are false ; both 

 true in some sense, and therefore reconcilable ; and both false through 

 narrowness of view, through exclusiveness, through mistaking a par- 

 tial for a general view. I can best illustrate my meaning by referring 

 you to the familiar but very instructive fable of the shield, which 

 being distinctly seen by two knights of equally good eye sight and of 

 undoubted veracity, was declared by one to be white and by the other 

 to be black. You will recollect that, after several lances were broken 

 and many wounds and bruises endured to decide the knotty point, it 

 was discovered by some one who, strange to say, was more interested 

 in the truth than in the dispute, that one side ivas ivhite and the other 

 was black. The disputants were both right and both wrong, but 

 wrong only by exclusiveness, by mistaking a partial for a general 

 view. So it is with almost all vexed questions. There is truth on 

 both sides, but both err in excluding the other. We are seeking in 

 the right direction when we attempt to show the partialness of both 

 views. We have risen to a higher view, to a philosophic truth, when 

 we show that these two partial and apparently irreconcilable views 

 may be united into one ; these two surface views may be stereoscopi- 

 cally combined. 



There is an old and much quoted adage, that " truth lies in the mid- 

 dle" between extreme opinions. As generally understood nothing 



