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value of the stratum would be two-fold, at all events it is 
worth considering. * In many places it could be readily ob- 
tained by quarrying, and as it often forms cliffs on the banks 
of rivers, as at Wainlode and Westbury, in Gloucestershire, 
and Aust Cliff, in Somersetshire, and on the Welsh Coast, 
(Pennarth,) which are liable to constant disintegration, the 
pieces could be easily collected and turned to good account, 
Most of the fish bone beds are of comparatively limited area, 
and often entirely local, as the one at the base of the Inferior 
Oolite, in the Gloucestershire Cotswolds; the most widely 
spread are the ones which belong to the Rheetic and Ludlow 
series. The latter is known to occur in its usual position in 
Gloucestershire, Herefordshire, and Shropshire. It rarely ex- 
ceeds an inch in thickness, is of a brown colour, very soft, 
and resembles ginger bread, and is made up of the commi- 
nuted fragments of placoid fish, (chiefly onchus,) coprolites, 
and crustaceans. For a long time these fish were supposed 
to be the earliest indications of their class, but within the 
last few years fish remains have been discovered in the 
Lower Ludlow rocks, still lower down in the Silurian, and 
therefore proving their existence at a much earlier period. 
This is only one of the many instances which prove how 
cautious we should be in drawing definite conclusions too 
hastily from mere negative evidence. The safest way is 
simply to state that as far as present discoveries have gone 
no traces of certain animals have been found lower down, 
* My friend Mr, Beesley has kindly analysed some specimens of the bone bed 
for me, and states that it contains 35 per cent of phosphate of lime, and that the 
bone is readily soluble in diluted Hydrochloric acid, whilst the sulphide is entirely 
inacted on. The thicker mass at Coombe Hill contains only 20 per cent. He 
suggests that the simplest plan of utilismg the Phosphoric acid would be to pour 
off the clear liquid, and use it as a liquid manure, adding first, if excess of acidity 
is an objection, milk of lime to complete the precipitaton of the Phosphate of lime. 
If the quantity was large, it might answer to burn it, producing sulphuric acid 
from the gases of its combustion, and then operating upon the residue with either 
hydrochloric acid, or sulphuric acid; or even it might be ground and applied at once 
to the land, as it would not be insoluble in carbonate water, like the so-called 
‘coprolites,’ and the residue of peroxide of iron would not be injurious to the land. 
The excess of Pyrites makes it undesirable to grind and apply it at once to the soil 
without some previous preparation. 
