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find in the Halifax formation, as complete a change from 

 marine to fresh water fossils in the same pit, as could pos- 

 sibly be presented to us. At one time we discover a 

 conglomeration of marine remains, as of Goniatites, Nautili, 

 Orthocerse, Pectens, and perhaps Belemnites, whilst a little 

 lower down in the same series, we come upon a whole stratum 

 of fresh water muscles, and these in such a perfect state of 

 preservation, as to lead us to the inference that they were 

 there embedded during a period of considerable tranquillity. 



The discovery of these unios superimposing the lower, or 

 soft bed, and the well known position of the marine animal 

 remains in those singular concretions, called by the miners 

 " Baum pots," immediately above the hard bed of coal, which 

 is five and twenty yards above the former bed ; — the abun- 

 dance of sulphur and iron in combination in the nodules, 

 popularly known by the name of " Brass lumps," interspersed 

 largely throughout the seam of hard-bed coal, which is 2 ft. 

 3 in. in thickness, and the total absence of those in the foot 

 and a half coal, or soft bed ; — the cessation of marine animal 

 remains after passing in descent through the hard bed, the 

 change to vegetable impressions alone, and then the extra- 

 ordinary fact of a stratum of unios lying beneath all these 

 upon the soft bed ; — and lastly, the almost non-fossiliferous 

 nature of the coarse gritty sandstone upon which this last 

 bed of coal rests, and, one might add, the total absence of 

 fossils in the lowest sandstone, or millstone grit, which sepa- 

 rates the next and last seam of coal, near Keighley, from the 

 limestone shale ; — these, I repeat, are facts which require 

 much consideration, but which will doubtless eventually tend 

 to throw considerable light upon this ancient formation ; and 

 I hope, at some future day, to be able to lay before you some 

 more lengthened remarks upon these interesting beds of coal 

 at Halifax. 



In the meantime, permit me to remind you that the forma- 



