230 



THE GEOLOGIST, 



used by them in 1860, nearly one hundred and ninety thousand were 

 Welsh coals. 



The various qualities stand as follows ; beginning with those which 

 have the greatest heating power. The column standing before the 

 name shows how many pounds of water can be converted into steam 

 by the use of a pound of the coal. The column C stands for the 

 carbon ; H for hydrogen, which is greatest in the bituminous coals, 

 and by its blaze adds so much to the cheerfulness of the fire-side. 

 Those coals that have most of it are caking coals, which is an addi- 

 tional attraction. Who does not like to poke the fire ? But when 

 stern work is to be done, and every ounce of coal is so much added 

 on to the price of iron — then the coal which has most carbon is in 

 request. 0, oxygen, is simply a nuisance ; for being combined with 

 (H) hydrogen, it forms so much water — a thing to be got rid of 

 before any heat can be got out of the coal. 



The best patent fuels have none of it, and Welsh coal has less than 

 Newcastle, and this than Scotch, as the table will show. My own 

 opinion is, that the further you go north, the more it takes to warm 

 you. 



Lbs. of Water. 



Best Coals. 



C. 



H. 



O. 



Ash. 



91 





911 



31 



2i 



H 



10^ 



Welsh, Ebbw Vale 



... 891 



5 



H 



H 



9, 4-5ths 





80 



21 





10 



n 





811 



6 



41 



3 



7 



Patent Fuels. 



741 



5 



151 



41 







90 



51 





3 



9 



Bell's 



87f 



5 





5 





Inferior Coals. 



80 



51 



61 



5 



8, 4-5ths 





75 



5 



5 



11 



81 





. , . 731 



51 



61 



10 



81 





641 



4f 



20f 



71 



We see by this table that a large quantity of oxygen and hydrogen 

 relatively to the carbon is a sign of inferiority ; and, of course, a 

 great amount of earthy matter, or ash, is so too. I will add, for 

 comparison, some substances which are not coal yet. 



C. H. O. 



Peat (from many analyses) 60 6 33 



Lignite (fossil wood and peat) 58 6 27 



Bogwood 57 6 37 



Willow wood 51f 6 41 



Oak 501 6 42 



Birch 501 6 42 



Beech 50 6 43 



The result is in round numbers : not quite exact. 



But then again, no kinds are useless. A coal that has most hydro- 

 gen is best for making gas ; and the coke will do for the furnace. 

 Parlour-coals should be more caking than those you allow for the 



