PnOOF.EDIXGS OF SOCIETIKS. 117 



allied to brown Metliill, formed from Acrogcnous plants, containing scalarifomi tissue, and an 

 abundance of vegetable j'cllow gas-giving matter apparently the altered contents of cells. 



PiioFESSOR GiiEGOiiY approved, in general, of the observations of Professor Balfour, and alluded 

 to some of the more special points in which he concurred. He then proceeded to consider the 

 subject briefly in its chemical aspect, in the first place noticing the changes in the plants' tissue 

 that were probably induced dui-ing the process of their transformation into coal. Coal was be- 

 lieved to be formed of vegetable matter, (the remains of plants,) in various ways, but chiefly 

 by a kind of fermentation taking place under great pressure. This would, of course, cause 

 changes in the cells and their contents, and probably the yellow inflammable matter was one 

 result of the process. In regard to that matter, which was, perhaps, more a resinous than a 

 bituminous substance, he thought Dr. Bennet was in error when he said that it was identical 

 with the inflammable bituminous matter used in Binny quarry. The Binny substance was quite 

 soluble in naptha, but no chemist had been able to say the same in regard to the yellow matter 

 of the Torbanehill mineral. With respect to the general chemical characters of that mineral 

 it did not differ in any essential point from Methil, and, perhaps, some other kinds of undoubted 

 coals. 



Dr. Wilson remarked that while Dr. Bennet had confined his paper chiefly to the peculiar- 

 ities of the Torbanehill mineral. Dr. Balfour had gone farther, and taken up the whole question 

 as to its relationship with different kinds of coal. Dr. Wilson submitted, however, that the 

 question before the meeting was not so much between the Torbanehill mineral and coal, as 

 between coal and bituminous shale, for the Society would be well aware that bituminous shale 

 was well known to the Germans as a commercial article, and the affinities of the Torbanehill 

 mineral seemed to lie in that direction. 



Dh. Douglas Maclagax desired an explanation of the opinions expressed by Dr. Bennet in 

 regard to the structures found in the brown, Methil, and Torbanehill coals. Dr. Bennet had 

 stated the fact, that scattered vessels, few in number, were found in the Torbanehill mineral 

 and in the brown Methil; he had also stated his conclusion that in the latter the structures 

 were normal, and that they pointed out the brown Methil to be coal, while in the Torbanehill 

 mineral they were merely accidental, and not to be regarded as affording evidence of the origin 

 of the substance. Dr. Maclagan wished to know the process by which Dr. Bennet had an-ived 

 at this conclusion, and whether there were any facts to support it. [Dr. Bennet replied, that 

 in the case of the brown Methil coal, the structures alluded to formed the organic basis of the 

 coal, which was not the case in the Torbanehill mineral, where they were merely accidental.] 

 At a subsequent period of the discussion. Dr. Maelagan again put his question. 



Professor Fleming regarded the remarks of Dr. Wilson upon bituminous shale, just as one 

 of those attempts to draw away the attention of the Society from the subject in hand, which 

 had been observed on a former occasion. He called attention to Dr. Bonnet's statement that 

 coal could not be formed of cellular tissue, without an intermixture of vascular to a large extent, 

 which he (Dr. Fleming) thought sufficiently answered by a fact he had detailed from his own 

 observation at a previous meeting of the Royal Society, namely, the formation of a bed of peat, 

 many feet in thickness, by a single cellular plant, having no vascular tissue whatever, Tri- 

 chostomiim lanuginosmn. There was another part of Dr. Bonnet's paper to which he would 

 allude. Dr. Bennet had stated that although a fossil bone or tooth was found in a rock, we 

 did not regard the rock as of animal origin; but Dr. Fleming reminded the Society that lime- 

 stone rocks often occurred, the great mass of which consisted of fossil shells, and in such cases 

 geologists did not hesitate to ascribe the origin or formation of the rock to these. 



Dr. Greville corrected a misconstruction that seemed to be put upon the evidence given by 

 him at the trial, in regard to the yellow bodies seen in the Torbanehill mineral. He was far 

 from saying that they were actual cells in their normal condition ; but in his own mind he was 

 perfectly satisfied that the mineral had a vegetable basis. This opinion was formed after a very 

 careful examination of numerous specimens. Seeing that there was so much difference of opinion 

 on this subject amongst scientific men, he thought it a great comfort to those of them who 

 had been examined on the trial, that the decision was not founded on their evidence. 



Dr. Bennet expressed a desire to see the specimens upon which the statements of some of 

 the speakers were founded, and stated his willingness to demonstrate, under the microscope, 

 the various facta in regard to structure upon which his conclusions were based. 



