112 DR. REDFERN, ON THE TORBANEHILL 



fossils, and that the same arrangement, in all its essential fea- 

 tures, exists in all of them and in the substance in which they 

 are imbedded, I think that good, if not altogether conclu- 

 sive, evidence is offered, that the bed of coal which contains 

 fossil vegetables, and has everywhere the same essential cha- 

 racters of structure and chemical composition as those fossils, 

 is itself a bed of vegetable matter. 



Let us now pass from these general observations to more 

 special ones, less easily made and understood. Cut a small 

 block of coal from the Torbanehill bed, say of one inch long, 

 two-thirds of an inch wide, and half an inch thick, so that its 

 upper and lower surfaces shall be exactly parallel to the sur- 

 faces of the whole seam ; polish its faces, and having coated 

 them with varnish, or covered them in turn with a drop of oil, 

 examine them with magnifying powers from 5 to 100 diameters 

 as opaque objects. The upper and lower surfaces of such a 

 block are alike, and the sides and ends are alike, but widely 

 different in appearance from the upper and lower surfaces. 



The top and bottom of the block are studded with more or 

 less rounded yellow spots, closely set in a darker mass ; the 

 sides and ends present a number of elongated yellow spots 

 in a darker mass. Such appearances are presented by the 

 surfaces of all such blocks, from whatever parts of the bed of 

 coal they may have been taken ; but they are least obvious in 

 the upper part of the seam, and are more easily recognised 

 the lower the part examined. These appearances I believe 

 to be produced by rounded yellow masses, flattened above and 

 below. 



There are also to be seen on ail such blocks irregularly 

 elongated and angular black patches, and branching black 

 lines, which run in various directions on the upper and lower 

 surfaces, but for the most part in the direction iu which the 

 coal splits on the sides and ends. Near the top of the seam, 

 crystals are seen scattered on all the surfaces of the blocks. 



The appearances presented by the surfaces of small blocks, 

 I think, have been mistaken in the case of other coals for 

 evidence of their consisting of woody tissue, whereas they are 

 merely the result of the laminar aggregation of the structures 

 of which beds of coal are formed. 



Let us for a moment examine the differences presented by 

 a block of wood and one of coal. If we take such a block as 

 that of which 1 have spoken from the trunk of a tree, so that 

 its upper surface would look towards the branches, and the 

 lower towards the root, these surfaces will present us with a 

 number of rounded openings and rings, which are the cut ex- 

 tremities of the vertical fibres and vessels of which the wood 



