198 Proceedings of the Royal Society of Edinburgh. [Sess, 
The extracts were obtained by treating the finely divided shale with 
pyridine in a Soxhlet extraction apparatus until the solvent siphoning over 
was no longer coloured, distilling off the pyridine at 60° C. under reduced 
pressure, transferring the semi-solid residue to a watch-glass and drying it 
in a vacuum desiccator over sulphuric acid. The extracts were dark brown 
in colour and showed a tendency to crystallise in radiating needles. They 
gave the following results on analysis : — 
Extract from Torbanite. 
(1) *0864 gave ‘0694 H 9 0 and *2590 C0 2 
(2) -0808 „ -0653 | „ -2467 „ 
(3) -0679 „ -0560 „ *2042 „ 
(4) *0684 „ -2088 „ 
0 = 81-75 
C = 83-26 
0 = 82-01 
0 = 83-26 
Average . . C = 82*57 per cent. 
*5031 gave "005023 N 2 N = l - 00 per cent. 
•502 „ -0138 BaS0 4 S = -38 „ 
H = 8-93 
H = 8-98 
H = 9-16 
H = 9-02 per cent. 
Extract from Broxburn Shale. 
•0726 gave -0768 H 2 0 and -2196 C0 2 
From Torbanite. 
0 82-57 
H 9-02 
N 1-00 
S -38 
(by difference) O 7*03 
100-00 
0 = 82*49 per cent. H = 11 -75 per cent. 
From Broxburn Shale. 
C 82-49 
H 11-75 
S > not estimated. 
These extracts are in all probability mixtures, as small proportions of 
them are dissolved by alcohol, benzene, etc. 
Action of Nitric Acid on Shales. 
Carrick Anderson (Jour. Soc. Chem. Ind., 1898, vol. xvii. p. 1018) 
described the action of nitric acid on coals, and gave analyses of the 
products obtained from seven different samples. These products are acids, 
and the product from any coal is always of constant composition provided 
an excess of acid is used. As it seemed possible that a comparison of these 
acids with any similar compounds which might be obtained from shales and 
other substances might throw some light on the origin and nature of the 
organic matter in shale, an endeavour was made to obtain similar deri- 
vatives from the following: — (1) Torbanite, (2) Broxburn shale, (3) New- 
battle cannel coal, (4) peat from Glenfalloch, (5) lycopodium spore dust, 
and (6) an organic sludge consisting mainly of decomposed leaf and root 
remains, microscopic algse, diatoms, and bacteria. From all of these, except 
