GEOLOGY. 319 



of vegetable matter. The author then remarked that the appearances of 

 small blocks of the Torbane Hill and other coals when examined as opaque 

 objects, and of their sections examined with higher magnifying powers, 

 are conclusive as establishing the fact that there are the most decided dif- 

 ferences in horizontal and vertical sections, and that these differences are 

 in no wise similar to those presented by sections made in different direc- 

 tions in a piece of wood. Wood consists of fibres and vessels for the most 

 part arranged parallel to each other, so that sections made in the direction 

 of the vessels and fibres show their sides in the form of strife under low 

 powers, whilst sections made across the fibres and vessels show a number 

 of rings which indicate the position of their ends. Horizontal sections of 

 a bed of coal show a number of more or less circular yellow spots set in a 

 dark mass, in great part composed of fragments of vegetable fibres and 

 membranes ; but all vertical sections show elongated yellow spots, separated 

 bv dark lines, running in the direction of the laminae of the bed of coal. 

 Had coal possessed a similar fibrous structure to that of wood, of two ver- 

 tical sections at right angles to each other, one would have shown a fibrous 

 appearance, the other a series of rings ; whereas there is never a difference 

 in vertical sections of coal in whatever direction these may be made. Dr. 

 R. especially directed attention to these conclusions, because they are di- 

 rectly opposed to those arrived at in a paper lately published in the 

 " Transactions " of the Microsopical Society of London. Sections exam- 

 ined by high magnifying powers show the lamina? of the Torbane Hill and 

 other Cannel coals to be made up of rounded yellow bodies, which are 

 flattened in the direction of the lamince, and contain their gas-giving sub- 

 stance. When the gas has been driven off by heat applied to a thin sec- 

 tion, a number of polygonal cavities are left. These are separated from 

 each other by very definite and consistent septa, many of which appear in 

 the substance of the larger yellow masses, and resemble the walls of vege- 

 table cells. In all parts of the Torbane Hill coal the author found a num- 

 ber of spherical or flattened membranous capsules of a reddish-yellow or 

 brown color, having tubercles and hairs externally, and smooth within. 

 These vary greatly in size, measuring from l-200th to the l-20th of an 

 inch in diameter. They appear to be spores, such as are commonly found 

 in large numbers in many common coals. 



The author concludes that all our coals may be arranged in a scale, 

 having the Torbane Hill coal at the top and anthracite at the bottom. An- 

 thracite is almost pure carbon ; Torbane Hill coal contains less fixed carbon 

 than most other Cannels ; anthracite is very difficult to ignite, and gives out 

 scarcely any gas. Torbane Hill coal burns like a candle, and yields 3,000 

 cubic feet of gas per ton, more than any known coal, its gas being also 

 of greatly siiperior illuminating power to any other. 



In Dr. R.'s opinion, the microscopical characters of coal point to its 

 having been formed on the spot in which we find it, to its being composed 

 of a mass of vegetable tissues, of various kinds, separated and changed by 

 maceration, pressure and chemical action, and to the introduction of its 



