76 Professor G. Forchhammer on the Donms of Denmark, 



a tract of country 140 English miles in length, and 70 miles 

 in breadth. 



The connection of the still living peat-moors with brown 

 coal and other coals through the link afforded by the Martorv, 

 unquestionably merits the attention of geologists. In the case 

 of coal, as in that of peat, the humic acid produced by the de- 

 struction of plants, extracts the iron from the soil in which it 

 is distributed, and collects it into a bed ; and it is remarkable 

 enough that the iron-beds of the coal formation of Wales, as 

 well as of other countries, contain titanium, as if the solution 

 of the titanic sand had taken place there, as it does in the case 

 now before us. In most peat a distinct stratification can be 

 recognised, as in the chief substance of the coal formation, the 

 slate-coal ; and it is quite reasonable to assume that the slaty 

 structure of the coal is derived from the yearly layers of the 

 vegetation of ancient peat-moors. Let us just reflect on what 

 would take place if a bed of moor-peat, covered with drift- 

 sand, were subjected to continued heat under high pressure. 

 The individual layers of the yearly deposits of the moor w ould 

 remain ; they would, however, diminish in size, by the substitu- 

 tion of the component parts, and by the removal of a portion of 

 the oxygen as carbonic acid, and we should, after the coal had 

 been formed, be able to discover the same layers, now become 

 thinner. This is exactly the case with slate-coal, and when we 

 examine the very thin layers, Ave perceive that the formation 

 in a period, which most probably was a year, is but extremely 

 inconsiderable, and that we must partly ascribe to length of 

 time what has been attributed to very rich vegetation. 



Even the phenomenon of the distribution of charcoal on the 

 stratified surfaces of peat is not awanting in the more ancient 

 coal ; and we have only to break up a piece of Newcastle coal 

 in order to discover everywhere, on such surfaces, mineral 

 charcoal (fibrous anthracite). Whence arose the forest- fires 

 at that period when no human beings existed who could ignite 

 the woods ? At present, lightning very often sets woods on 

 fire, and probably did so at that epoch. 



In order to render complete the analogy with the older for- 

 mations, we frequently find, in the moor-peat beds of Skagen, 

 flattened branches and stems of birch. This arises from the 



