200 
Proceedings of the Royal Society of Edinburgh. [Sess. 
Acid from Peat. 
•0557 gave *0274 H 2 0 and ’1081 C0 2 0 = 52*93 per cent. H = 5*47 per cent. 
•0976 „ *004477 N 2 N = 4-59 per cent. 
Acid from Lycopodium. 
(1) *1051 gave -0891 H 9 0 and -2334 C0 2 C = 60 56 H = 9*42 
(2) -1006 „ *0848 „ *2204 „ C = 59*75 H = 9*37 
Average . . C = 60 ’15 per cent. H = 9-39 per cent. 
(1) -4966 gave *01904 N 2 N = 3*83 
(2) *5106 „ *01916 „ N=3*77 
Average . . N = 3*80 per cent. 
Acids obtained from Shales, etc. 
Torbanite. 
Broxburn 
Shale. 
Cannel Coal. 
Peat. 
Lycopodium. 
c 
61*26 
59*62 
53*61 
52*93 
60*15 
H 
7*42 
6*72 
5*44 
5*47 
9*39 
N 
4*37 
4*29 
3*92 
4*59 
3*80 
O 
(by difference) 
26*95 
29*37 
37*03 
37*01 
26*66 
100*00 
100*00 
100*00 
100*00 
100*00 
The estimation of the metallic radicals in the silver and ammonia salts 
of the acids from torbanite and Broxburn shale confirm these analyses, and 
point to the empirical formulae : — 
From : — 
Torbanite. Broxburn Shale. Cannel Coal. Peat. Lycopodium. 
c 16 h 24 no 5 c 16 h 22 no 6 c 16 h 19 no 8 c 13 h 17 no 7 c 19 h 35 no 6 
The empirical formulae calculated from Carrick Anderson’s coal-acid 
analyses are : — C 14 H 9 N0 6 (Ell) ; C 15 H 9 N0 5 (Splint) ; C 15 H 9 N0 5 (Gas) ; 
C l7 H 10 NO 7 (Virgin); C l7 H 10 NO 6 (Lower Drumgray); C 16 H 10 NO 6 (Bannock- 
burn Main); and C 21 H 13 N0 8 (Kilsyth Coking). 
These substances, which are evidently all of the same nature, can be 
arranged into a series commencing with lycopodium acid where the 
hydrogen is relatively highest, and passing through torbanite, Broxburn 
shale, peat, and cannel coal-acids to ordinary coal-acids where the hydrogen 
is relatively lowest. It being recognised that the first and last terms of the 
series represent derivatives of pure vegetable matter and of highly meta- 
morphosed vegetable matter respectively, the probable conclusion is that 
the intermediate terms represent different stages in the alteration of 
vegetable matter. This does not, of course, infer that the process of change 
