202 
ANNALS NEW YORK ACADEMY OF SCIENCES 
Whether or not this delta theory explains all of the coal measure phe¬ 
nomena, even whether or not it explains those of the little basin of Commentry, 
is not, as the reader must have recognized, an open question in the writer’s 
mind. But be that as it may, Fayol is wholly accurate in stating that the 
theory, as presented by him, is not absolutely new for it is quite old. One 
can hardly believe that Jukes’s brilliant work, first published prior to 1850 
and republished in 1859, 1 had been forgotten in 1889; yet there is no doubt 
that it was then unknown to many eminent geologists in France and that 
it is still unknown to some who are engaged in the investigation of coal 
phenomena. 
Unquestionably, as Fayol says, the greater number of geologists who have 
devoted themselves to the study of coal, have not accepted the doctrine that 
coal is derived from transported vegetable matter; but there have been very 
few who did not see in the structural arrangement of materials full evidence 
of delta deposit; many of the phenomena, described by Fayol in such 
detail, have been regarded by others as, so to say, elementary facts, deserving 
mostly of only passing reference. But Jukes in his discussion went farther 
and applied the laws of delta deposit to transported vegetable matter in 
order to account for the origin of coal beds themselves — and his arguments 
are very largely the same as those employed by Fayol, 40 years afterwards. 
Certain features in some of the important coal beds led Jukes to say, 
“ they have only confirmed me in my belief in the entirely subaqueous deposi¬ 
tion of these coals.” He bases his opinion upon 
the “rolls,” “swells” or “horsebacks” in the coal, 
the “rock faults” or great masses of sandstone in the coal, 
the branching of coal beds, 
the expansion of coal beds toward the direction whence the mineral 
materials came. 
He discusses fully the distribution of mingled materials and asserts, the 
italics being his own, “It appears to me that the phenomena of lamination 
and stratification of beds of coal and their interstratification and association 
with other stratified rocks are explicable solely by the relation of the specific 
gravity of their materials to the action of moving water, and the consequent 
diffusion of those materials through the mass of that water.” 
The variation in thickness and other changes in the coal beds “are 
distinctly referable to the action of water in transporting materials of different 
kinds which have been committed to it”: and further he insists on “the 
obvious ‘delta-like’ or ‘bank-like’ form which the coal measures of South 
1 Jukes, J. Beete: The South Staffordshire Coal Field. Mem. Geol. Survey of Great 
Britain, 2d. edition, pp. 202-206. London, 1859. 
