TRANSACTIONS OF THE SECTIONS. 37 
to it another of sulphocyanide of potassium, a sulphocyanide of the former metal, 
in long white crystals, falls. 
This is necessarily a very imperfect paper in an exclusively scientific point of 
view. Both the writer and his friend M. Brivet had been too much occupied in 
other affairs connected with the Meeting to devote that time to its preparation the 
interest of the subject entitles it to. The results were in consequence confined to 
rocuring the salts, and any further examination of them must be reserved for the 
uture. The results already obtained, indeed, were somewhat abridged by the in- 
disposition of M. Brivet, occasioned by frequent contact with the metal, or rather in 
breathing its fumes; at all events, his symptoms, those of languor and headache, 
corresponded with those already described by another dperator. 
On Minerals and Salts found in Coal-pits. 
By R. Carvert Crapnam and Joun Dacuisx, F.GS. 
In conducting the extensive coal-mining operations in the counties of Northum- 
berland and Durham, many interesting minerals and salts are met with, which are 
little noticed by mine-adventurers, as they do not bear directly on the material sought 
for. Some of these substances have been formed simultaneously with the coal, or 
at least at periods far removed from the present time, whilst others are of recent 
formation. Having had favourable opportunities of obtaining and examining spe- 
cimens, the writers proposed briefly to describe the results, and, in doing so, divided 
the paper into the following heads :— 
1. Coal, and, 
2. The adjoining rocks which were formed nearly simultaneously with it. 
3. The minerals and other foreign substances found in coal. 
4, The salts found in coal, and formed by decomposition and recombination. 
1. Coal.—One of the most striking peculiarities of the northern coal-tield is the 
variety in the economic quality of the various beds of coal—the same seam being 
in different parts a household, a gas, a coking, and a steam coal; and this occurs 
without any great alteration in its chemical constituents, and probably arises from 
a different combination of elements or in mechanical structure. 
The household coal has a hard fracture, and in burning leaves little ash, and that 
of ared colour. The essential economic character of gas coal is the yielding of a 
large quantity of gas on distillation, together with freedom from sulphur and other 
eepmtice. The requisite of coking coal is that, on roasting in close ovens, it should 
yield a hard and compact coke, free from sulphur and from slaty particle, which, 
on burning, would leave clinkers and destroy the fire-bars. The steam coalis a very 
hard, free burning, white ash, non-caking coal. 
2. The Rocks adjoining the Coal consist chiefly of bituminous and non-bituminous 
shales, sandstone, ironstone, and limestone; and although they possess numerous 
distinctive features of very great interest, a lengthened description would be 
foreign to the purpose of this paper, and is the less required, as their general pro- 
erties have been frequently described and are well understood. Specimens were 
Reaves exhibited, and a brief analysis of each annexed, for the object of showin 
more clearly the part they play in the formation of the salts, &c., hereafter to be de- 
scribed. The following are the specimens selected :— 
1. Specimen of non-bituminous shale, from Messrs Cowen’s Pit, at Blaydun. 
2. Specimen of blue shale, from Newsham Colliery, near Blyth. 
8. Specimen of bituminous shale, from ‘the roof of the Low Main or “ West 
Haslay ” seam, at the same mine. 
4, Specimen of mussel-band ironstone, from a bed lying five feet above the 
ait Main seam, in the Bedlington Pit, and clay-ironstone, from Hetton 
olliery. 
5. Specimens of sandstones used for building up-cast shafts. 
The specimens of sandstone were from various well-known quarries in the coal- 
“measures. 
The chief characteristic of these sandstones seems to be the quantity of iron, 
lime, or magnesia they contain, which is the cause of their decomposition when 
exposed to the action of disintegrating agents, and has led to serious loss through 
