274 Notes and Comments. 



Slack from Bituminous Yorkshire Coal. 



Yield of crude oil — 24 gallons per ton of coal carbonised. 



Yield of sulphate of ammonia — 22 lb. 



The oil on fractionation yielded : 



Oil distilling to 170° C 2.8 gallons 



Fuel-oil 12.0 



Paraffin wax ... ... ... ... not determined. 



A RIVER OF THE COAL AGE. 



During the winter, Professor P. F. Kendall, in a lecture to 

 the Leeds Philosophical Society on ' Rivers of the Coal Age.' 

 described the courses of some of the streams fertilising the 

 great deltaic plain on which were accumulated the materials 

 of the coal seams of the Yorkshire coalfield. Recently the 

 members of the Yorkshire Geological Society had an opportun- 

 ity under Professor Kendall's guidance, of visiting and examin- 

 ing the traces of some of these streams in the workings of the 

 Ackton Hall Colliery, Featherstone. When the shaft of the 

 pit was originally sunk, 24 years ago, the important Silkstone 

 seam (as that which is elsewhere called the Middleton Main 

 seam is locally called) was passed through without recognition. 

 It was subsequently found that the shaft was situated in an 

 area in which the coal had been seriously thinned by stream 

 action of Coal Measure times. With the development of the 

 workings it has been shown that throughout the length of the 

 Actkon Hall estate — about three miles — there is a tract of a 

 quarter of a mile wide, evidently the bed of a stream, where the 

 Silkstone seam is altogether removed, and its place filled with a 

 valueless sandstones and mudstones. Besides the great ' wash- 

 out ' (which was no doubt the effect of a river of a phase a 

 httle later than the deposition of the seam), relics were examined 

 of a river which was strictly contemporary with the seam itself. 

 This smaller river is marked, not by the total removal of the 

 coal, but by the intercalation in the midst of the seam of a 

 mass of river sands and muds. The intrusion is several times 

 as thick as the complete seam, this being due to the great 

 compression which the coal has undergone, and to the relative 

 incompressibility of the sands. Other curious features which 

 threw light on the physical condition prevailing in Coal-Measure 

 times were examined. In one part of the mine, in an air- 

 passage unfrequented by the miners, was a very beautiful 

 display of ' stalactites,' formed mostly of common salt. 



THE BRITISH ASSOCIATION. 



Referring to our remarks respecting the postponed meeting 

 of the British Association, which were also voiced at the 

 recent Conference of Delegates in London, we understand that 

 there is a possibility of a meeting of the British Association 

 being held during 1919. The invitation to visit Bournemouth 

 which was made last year still holds good, but if that place is 



Naturalist, 



