H. B. Woodward—WNotes on Jurassie Rocks. 467 
all, as it seems to me, have ended in failure. Till we know the rate 
of causation in the past, and until we can be sure that it has been 
invariable and uninterrupted, I cannot see anything but failure in 
the future. Neither the rate of the erosion of the land by subaérial 
agencies, nor its destruction by oceanic currents, nor the rate of the 
deposit of stalagmite or of the movement of glaciers, have as yet 
given us anything at all approaching a satisfactory date. We only 
have a sequence of events recorded in the rocks, with intervals the 
length of which we cannot measure. We do not know the exact 
duration of any one geological event. Till we know both, it is 
surely impossible to fix a date, in terms of years, either for the first 
appearance of Man or for any event outside the written record. We 
may draw cheques upon ‘The Bank of Force” as well as on “The 
Bank of Time.” 
Two of my predecessors in this chair, Dr. Woodward and Professor 
Judd, have dealt with the position of our science in relation to 
Biology and Mineralogy. Professor Phillips in 1864 pointed out 
that the later ages in Geology and the earlier ages of mankind were 
fairly united together in one large field of inquiry. In these remarks 
I have set myself the task of examining that side of our science 
which looks towards History. My conception of the aim and results 
of Geology is, that it should present a universal history of the 
various phases through which the earth and its inhabitants have 
passed in the various periods, until ultimately the story of the earth, 
and how it came to be what it is, is merged in the story of Man and 
his works in the written records. Whatever the future of Geology 
may be, it certainly does not seem likely to suffer in the struggle for 
existence in the scientific renascence of the nineteenth century. 
IIJ.—Tue Rewarions oF THE GREAT OoxiTE To THE Forest MARBLE 
AND FULLER’S-EARTH IN THE Sours-west oF Ena@uanp. By 
Horace B. Woopwarp, F.G.8., of the Geological Survey of 
England and Wales. 
[Communicated by permission of the Director-General of the Geological Survey. ] 
HE southerly attenuation of the Great Oolite, and its absence in 
Dorsetshire, have been generally attributed to lateral changes 
in the strata—it being considered that the Great Oolite is mainly 
replaced by Forest Marble (which has been stated to increase in 
thickness southwards), and perhaps in part by the Fuller’s-earth. 
In Gloucestershire the Great Oolite and Forest Marble are so 
interblended that there is no real line of demarcation. At Bradford- 
on-Avon this is not the case: the surface of the Great Oolite, with 
its clusters of Apiocrinus, indicates a pause in deposition, and we 
have locally a good line of division between this formation and the 
Bradford Clay, which is a subordinate portion of the Forest Marble. 
Southwards the Bradford Clay horizon extends to the Dorsetshire 
coast, but the Great Oolite is no longer found, and we see no evidence 
of the Crinoid growth in situ. The estimated thickness of the Forest 
Marble in Dorsetshire has been much exaggerated, and the evidence 
