180 



AQUEOUS BOCKS 



parts of North America. .An impure variety containing a eon- 

 siderable quantity of siliceous sand, and locally known as 

 '^muck," is used as a fertilizer and for mulching throughout 

 New England. On page 129 are given the results of analyses of 

 (I) peat from the bog of Allan, Ireland, (II) Commander 

 Islands in Bering Sea, and (III) Maine (United States). 



Lignite, or brown coal, is the name given to a brownish black 

 material characterized by a brilliant lustre, conchoidal fracture, 

 and brown streak. Such contain from 55% to 65% of carbon, 

 and burn easily, with a smoky flame, but are inferior to the true 

 coals for heating purposes. 



Bituminous Coal. — Under this name are included a series of 

 compact and brittle products in which no traces of organic 

 remains are to be seen on casual inspection, but which, under 

 the microscope, often show traces of woody fibre, spores of 

 lycopods, etc. These coals are of a brown to black color, with 

 a brown or gray brown streak, break with a cubical or conchoidal 

 fracture, and burn readily with a yellow, smoky flame. They 

 contain from 35% to 70% of fixed carbon, 18% to 60% of vola- 

 tile matter, and from 2% to 20% of water, and only too fre- 

 quently show traces of sulphur due to included iron pyrites. 

 Several varieties of bituminous coals are recognized, the distinc- 

 tions being based upon their manner of burning. Coking coals 

 are so called from the facility with which they may be made 

 to yield coke. Other varieties of apparently the same com- 

 position and general physical properties, cannot, for some 

 unexplained reason, be made to yield coke, and are known 

 as non-coMng coals. Cannel coal has a very compact struc- 

 ture, breaks with a conchoidal fracture, has a dull lustre, 



Chemical Composition of Coals 



CONSTITaENTS 



I 



11 



Water 



1.105% 

 29.885 

 57.754 



9.895 



1.339 





Volatile matter 



58.00% 

 23.50 



Fixed carbon 



Asli 



18.50 



Sulphur 











99.978% 



100.00% 



