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whether any analogy exists between the flora of this and the 
Oolitic Coal fields ? and lastly, whether all coal fields have 
been deposited under 'the same conditions ? Surely these 
questions are not without universal interest to gentlemen who 
live in the heart of a large Coal district, and whose best 
interests, as I before said, are so much bound up and identi- 
fied with all that may add to the better and clear under- 
standing of the strata from which our minerals are derived. 
Mineralogy — 
An extensive collection of all the Minerals in the 
Coal field. 
1st. Of Coal.— We should have specimens sent from each 
workable seam in the district ; but by this I do not mean that 
one specimen from each seam will be sufiicient, we should 
have all the varieties, and there are many, found in each 
seam. Take for instance, the Barnsley Thick coal : one spe- 
cimen from this seam would not present all the characters 
that are observed in it. In transmitting samples of coal, 
great care should be taken to describe their property ; whe- 
ther they are caking or free burning coals; whether the ashes 
are white or brown. 
Seams of coal may be searched for resins, which they 
sometimes contain. 
Again, it may be inquired, under what circumstances is 
Cannel coal met with? Does it only occur in particular 
seams, or in all seams ? Does it pass into common Coal, and 
at other times into Bituminous Shale ? Why do certain 
fossils always accompany Cannel Coal ? Many other ques- 
tions of a similar nature cannot be answered, unless we have 
before us a large collection for examination. 
Then, again, looking to other Coal fields, we may hope to 
obtain from them many treasures with which to compare our 
own, and correct our previously formed opinions. 
But above all, it is essentially necessary to have Coal in all 
