TORBANEHILL MINERAL AND OF VARIOUS KINDS OF COAL. 185 



Description of the Plates. 



Plate I., Fig. 1. Transverse section of Buccleuch or Dalkeith coal, magnified 80 diameters linear. 

 It displays imbedded in the bistre-brown mass, 1st, The rings described in the 

 text ; 2dly, The reddish masses supposed to be resin cells ; and, 3dly, The 

 large circles considered to be sections of spore cases. 



Fig. 2. Another portion of the same section, magnified 200 diameters linear, showing- 

 more particularly the appearance of the rings held to be characteristic of coal. 



Fig. 3. Longitudinal section of the same coal. 200 diameters linear. 



Fig. 4. Transverse section of the Wemyss cannel coal, showing, in addition to the rings, 

 several bituminoid masses. 200 diameters linear. 



Fig. 5. Longitudinal section of the Wemyss cannel coal. 200 diameters linear. 



Fig. 6. Transverse section of the Lesmahagow cannel coal, showing a less number of the 

 rings, but a greater number of the bituminoid masses. 200 diameters linear. 



Fig. 7- Longitudinal section of the Lesmahagow cannel coal. 200 diameters linear. 



Fig. 8. Transverse section of the Brown Methil coal, showing very few of the rings, but a 

 greatly increased number of the bituminoid masses. 200 diameters linear. 



Fig. 9. Longitudinal section of the brown Methil coal. 200 diameters linear. 



Fig. 10. Transverse section of the darker coloured Torbanehill mineral, showing the bitu- 

 minoid masses imbedded in clay. No rings are anywhere visible. 200 diameters 

 linear. 



Fig. 1 1 . Transverse section of the lighter coloured Torbanehill mineral, showing the deep 

 orange-coloured masses, and the melting together of the bituminoid masses. 200 

 diameters linear. 



In these sections it will be observed, that common coal abounds in the rings, 

 and possesses no bituminoid bodies. The cannel coals have rings and 

 bituminoid bodies, whilst the Torbanehill mineral is principally composed 

 of the bituminoid masses without any rings at all. It will be further seen, 

 that in different cannel coals these various elements vary greatly in 

 amount. 



Fig. 12. Transverse section of the Torbanehill mineral, at the upper portion of the seam, 

 where veins of coal run through it. 200 diameters linear. 



Plate II. Fig. 1. Bituminoid masses imbedded in the clay of the Torbanehill mineral, at the edge 

 of a section, magnified 750 diameters linear, to show their radiated texture, 

 and mode of fracture. 



Fig. 2. Section of the lighter coloured Torbanehill mineral, in which a plant is imbedded, 

 , showing the scalariform vessels. 200 diameters linear. 



Fig. 3. Ashes of the Zetland coal, showing mineral masses and spicula, black fibres and 

 plates, perforated with round openings. 200 diameters linear. 



Fig. 4. Ashes of the Torbanehill mineral, showing their amorphous structure. 200 

 diameters linear. 



VOL. XXI. PART I. 3D 



