560 Transactions. — Chemistry and Physics. 



3. Brown Coal of the 8ft. Seam. 



This is a compact fairly hard coal, which weathers well, 

 and is in every way superior to the average coal of the district. 

 • Mr. Page, of the chemical department of Canterbury College, 

 kindly placed at my disposal a sealed specimen of the altered 

 brown coal from the old Brockley working, so that I was 

 enabled to compare it directly with the coal now being got 

 out. The comparison showed that the coal-substances of the 

 two are very much alike. The present coal, being near the 

 surface, contains, however, as would be expected, more ash and 

 more water per cent, than the old. Already, as the drive gets 

 further in, this proportion of ash is lessening. The coal burns 

 well, and is almost entirely free from the fetid odour so notice- 

 able with many of the Malvern " browns." 



Origin of the Anthbacite. 



The anthracites of Europe and America are almost uni- 

 versally held to represent the final stage of that natural pro- 

 cess of destructive distillation which has given us the whole 

 range of brown and bituminous coals. The reason for the 

 change is in some instances fairly obvious ; in many others, 

 however, still a mystery. 



Generally speaking, we may divide the main a^ithracite 

 beds into three groups — (1) Those apparently due to the direct 

 action of heat ; (2) those apparently due to the direct action of 

 pressure (and heat?); and (3) those whose .origin is still un- 

 accounted for. 



To the first class belong the smaller anthracite seams in 

 the neighbourhood of igneous dykes and floes. That these 

 dykes actually alter ordinary coals in the direction of anthra- 

 cite is a well-established fact. 



Woodward,* in speaking of the various characteristics of 

 the South Staffordshire Coalfield, says, "The Eowley Eag 

 basalt is well known in connection with the district ; accord- 

 ing to Jukes it forms part of the coal-measure series, having 

 been poured out as a sheet of lava during this period. The 

 coal beneath the basalt has been altered, and has lost its 

 mfiammability . " 



Again, " The Cleveland, Cockfield, and Annathwaite dyke 

 commences six miles south of Whitby, and extends . . . 

 more than ninety miles. . . . It is probably of Tertiary 

 age. In some localities where it does not reach the surface 

 it has been proved in colliery workings ; but the coal in 

 proximity to the eruptive rock becomes anthracitic, and 

 ultimately v^orthless." 



Professor Hull mentions that at Whitwick a sheet of 



• " Geology of England and Wales," by H. Woodward, p. 189, &o. 



