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re- construction of geography as we have seen here. Here (point- 

 ing to a map) we have the coal seams occupying the position of 

 the old shingle bed of the lower carboniferous times. In Ireland 

 in those days there was a wonderful wealth of growth, and in 

 those times you might have walked straight away from this 

 island of ours into the region of Ireland over a dead alluvial flat 

 covered by these forests traversed by innumerable winding rivers, 

 some of which are preserved abundantly, and some of which we 

 can map in the Forest of Dean. Thus then you see the geogra- 

 phy of this country at this time was in strange contrast to that 

 geography which I have put before you in deahng with the 

 Archaian portion of our subject. There was no Pennine Chain in 

 those days, and no hiUs in this part of the country. Here in 

 Bui'nley you have enormously thick coal measure rocks, rather 

 less than half the total thickness of these successive level growths. 

 In the Wigan coal fields we have a thickness altogether of 7,200 

 feet of sand bank and mud bank, and forest growth. Only just 

 consider what time that means ! We know at the present day 

 that the accumulations of sand, say in the Irish sea, is excessively 

 slow. Why there has been no important addition to our island 

 formed by the accumulation of sand since the days that the 

 Romans landed here ! We know, too, that the deposit of mud 

 is also very slow. How long then, may we ask ourselves, was 

 required for the accumulation of 7,200 feet of deposits largely 

 formed of sand and of mud ? Or, supposing we put it in another 

 way, how long would it take to form a foot of coal ? A foot of 

 coal would represent I am afraid to say how many feet of com- 

 pressed vegetable matter. How many forests of trees lived and 

 died upon a given spot of coal seam ? All these facts bring us 

 face to face with the problem of the infiniteness of past times. 

 But now let me point out to you the wonderful series of 

 physical revolutions which took place at the close of the carbon- 

 iferous age. At the close of the carboniferous age these great 

 horizontal tracts, clad with forests, were thrown into a series of 

 folds, formed at the close of the carboniferous age and before 

 any of your rocks were formed. I take it that the fold of which 

 Pendle Hill is one of the most remarkable monuments in this 

 district, took place at approximately the same date, and I know 

 for certain that there was another series of folds extending right 

 away from the west of Ireland, all through Somerset, to the 

 Belgian coal fields, an enormous smashing and crashing at right 

 angles owing to these operations. Then broke up the vast tract 

 of coal formation into a series of isolated coal fields of which the 

 present coal fields are mere rags and tatters. It almost makes 

 me shudder to think of the enormous amount of coals which 

 Ireland has lost by the erosive action of the ice, the atmosphere, 

 and the like. In ancient times Ireland was richly endowed with 



