I9II.] STEVENSON— FORMATION OF COAL BEDS. 81 



pounds less rich in carbon going farther. But the relations lead 

 to a chemical impossibility ; " a " gives CgH^o, while the coal gives 

 practically CieH^o- 



The reason is that not all of the water of hydration goes off at 

 120°. To escape this error, Spring employed hydrofluoric acid and 

 continued the solution until the ash was about 10 per cent., the same 

 with that of many coals. Analysis of the residues gave these ratios ; 



"a" "b" "c" "d" '' e " i 23 



C:H 24.80 30.45 36 ? ? i9-8o ? ? 



The results for " d "' and " e " are uncertain as are also those 

 for 2 and 3, the hydrogen being present in such small quantity. De- 

 termining the absolute relation of hydrogen he has 



Coal 'a." "b" "c" " d " "e" i 2 3 



Carbon 88.61 7.54 3.35 2.21 1.20 0.70 0.99 0.93 0.80 



Hydrogen 4.65 0.30 o.ir 0.06 ? ? 0.05 ? ? 



C : H 19.09 24.28 30.45 36.00 ? ? 19.80 ? ? 



The relation of carbon and hydrogen in the mur is very nearly 

 the same as in the coal; it contains particles of coal little altered. 

 But the toit results are remarkable ; the hydrogen diminishes in 

 relation to the carbon and in " d " and " e " it is no longer in appre- 

 ciable quantity. Evidently the roof shales are not impregnated by 

 volatile materials coming from the coal, as required by Fremy's 

 theory. The transformation of the vegetable matter is rather by 

 ulmic fermentation. Within the primitive marshy mass the plant 

 substances have yielded ulmic materials while becoming richer in 

 carbon. These have impregnated the whole and have been modified 

 by external agencies. 



The doctrine of transport seems to be out of harmony wath the 

 results as by it one would have difiiculty in explaining the richness 

 in carbon characterizing the toit. The alluvium, because of its 

 physical nature, could not support a sufficient vegetation. If one 

 suggest that the alluvium at its origin was mingled with much vege- 

 table debris, it may not be superfluous to ask if the plants could 

 remain on slopes, denuded and torn up by the flood which had swept 

 away the most thoroughly rooted plants. Everything speaks of 

 origin in situ. But returning to the analyses. 



PROC. AMER. PHIL. SOC, L. I98 F, PRINTED APRIL 25, IQII. 



81 



