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KENDALL : PRESIDENTIAL ADDRESS. 
Impelled by such a momentum on both its biological, and its 
physical side, our science entered upon that half century of 
progress that I shall endeavour very broadly to trace. 
Let us look first at Stratigraphical Geology. 
The whole of England has been mapped by the official 
Geological Survey, the Coalfields and much of the Yorkshire 
Coast on the six-inch scale, and in this work, or aided by the maps, 
the great formations have been divided into smaller sub -divisions, 
and these in many cases into smaller still, so that, like the Green 
Streak," in our Silurian rocks, even a layer an inch in thickness, 
if a significant inch, is not disregarded. The last work that Sorby 
published — written, or dictated, when he was lying upon his 
death-bed — was an attempt to show the time-equivalent of an 
inch of sediment. 
We have come to see that deposits may be laid down very 
rapidly in one place, and very slowly in another, so that an inch 
of Red Clay or Radiolarian Ooze might represent a period of 
continuous deposition that found expression elsewhere in a 
thousand feet of shallow water deposit. 
In Stratigraphical Palaeontology the principles of Zoning 
have been applied with extraordinary success. 
The first piece of minute zoning accomplished in Britain Avas 
in the Lias. The principles were quickly applied in Yorkshire, 
but the major part of the work had alread}^ been done in the 
Cotswolds, and in that splendid work of Judd's the Geology of 
Rutland. Then, following the Lias, the Oolites were zoned, and, 
at a long interval, it was discovered that the Chalk was also 
amenable to the zonal method. Mr. Caleb Evans, working 
along a derelict railway near Croydon, found that the Southern 
Chalk was separable into fairly weU-defined horizons hy distinc- 
tive fossils, such as Brachiopods, Lamellibranchs, Cephalopods, 
and Echinoderms. It was my good fortune as a young man to 
be sent to trace these zones on the same line of section and my 
first published paper resulted from observations then made. 
The zoning of the Chalk was a very important achievement, 
as the lithology varies from place to place, and the lithological 
characters cross over from Upper to Middle and vice-versa in a 
manner that defies analysis without the aid of the fossils. Our 
