200 



On comparing the latter with the accompanying specimen of 

 the Finns australis of the present day, its close resemblance is 

 very evident, it fitting the impression almost as if moulded from 

 it. On the side of the recent specimen, adjacent to the axis of 

 the branch, is a protuberance formed by the vessels which pene- 

 trate the bark, and depressions on each side thereof, to which 

 the impressions of those in the Shale, although faint, bear a 

 close resemblance. In many of the leaves of the recent fir tribe 

 there are rows of glands extending from the base to the summit, 

 and, in some, very minute spines on each edge ; it cannot be ex- 

 pected that these microscopic characters should be visible in 

 impressions on so coarse a material as the Shale, but no doubt 

 they will be found when similar impressions are discovered in 

 the coal itself. 



Other impressions of leaves of Coniferse are in my Collec- 

 tion, some in the Anthracite, but although I have no doubt of 

 their being leaves, they are not so undeniable as to be exhibited 

 as proofs. I pass on to the Chemical evidence. Lehmann, in 

 his Physiological Chemistry states, that formic acid is found in 

 coal during the process of decay (eremacausis) and also that it is 

 found in the berries of the Juniperus and in the cones of several of 

 the fir tribe. Redtenbacher finds formic acid in the leaves and 

 twigs of the fir tribe during fermentation (incipient eremacausis.)" 

 A few years ago, Pelletier and Walther examined the tar pro- 

 duced by the distillation of resin, and found therein two sub- 

 stances, which they named retinnapiha and retinnyle, and then 

 the well known napthaline. 



The progress of Organic Chemistry has since shown the two 

 former substances to be the Toluole and the Cumole of the pre- 

 sent day. In 1849, Mansfield, at the instigation of Dr. A. W. 

 Hoffmann, investigated the products of the distillation of the coal 

 tar from gas works, chiefly, however, with the view of ascertain- 

 ing the boiling points of the various educts. He tabulates the 

 neutral results of his distillations as follows : — 



1. Benzole, Ci2 He 



2. Toluole, C 1 4 H8 the retinnaptha ) ^^ p^^^^^.^^. ^^^ ^^^^^^^ 



3. Cumole, Ci8 H12 " retmnyle ) 



4. Cymole, C20 Hi* 



and then Napthaline. 



I will now simply advert to the opinion of Goppert, in his prize 



