oe 
Professor T. G. Bonney—Glacial History of W. Europe. 463 
with that of the Bunter, which was formed by a river coming from 
North-West Scotland. 
21. There is a correspondence between the characteristics of the 
micropetrography of the Bunter, Keuper, and modern delta formations. 
The Leicestershire Trias shows signs of chemical action, the Nile delta 
of mechanical. The chemical composition of volcanic and metamorphic 
rocks locally argues a local as well as a distant source for the heavier 
minerals of the Keuper. 
22. The evidence of the flora and fauna shows that there were 
provinces, and these were so arranged as to allow for the prevalence 
of delta conditions. The climate was moist and equable. 
Finally, we conclude that there is nothing to prove that desert con- 
ditions did anything more than locally act upon the rocks mechanically, 
and to some extent chemically. They had no part whatever in the 
work of deposition; that is to say, they disintegrated the previous 
rocks (pre-Trtassic). There is positive, direct, and accumulative 
evidence to prove that the Trias as a whole (and not the Bunter only) 
was the work of rivers which had continued to bring sediment in one 
form or another from the north-west of Britain or the north more or 
less continuously, under one condition or another, from the close of 
the marine phase of Lower Carboniferous (Mountain Limestone) times. 
NOTICEHS OF MEMOTRS. 
Sse 
I.—British ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE. 
SHEFFIELD, 1910. Appress by the Rev. Professor T. G. Bonney, 
se.D., LL.D., F.R.S., President.? 
DO not propose, as you might naturally expect, to discuss some 
branch of petrology; though for this no place could be more 
appropriate than Sheffield, since it was the birthplace and the life- 
long home of Henry Clifton Sorby, who may truly be called the 
father of that science. This title he won when, a little more than 
sixty years ago, he began to study the structure and mineral 
composition of rocks by examining thin sections of them under the 
microscope. A rare combination of a singularly versatile and active 
intellect with accurate thought and sound judgment, shrewd in 
nature, as became a Yorkshireman, yet gentle, kindly, and unselfish, 
he was one whom his friends loved and of whom this city may well 
be proud. Sorby’s name will be kept alive among you by the 
Professorship of Geology which he has endowed in your University ; 
but, as the funds will not be available for some time, and as that 
science is so intimately connected with metallurgy, coal-mining, and 
engineering, I venture to express a hope that some of your wealthier 
citizens will provide for the temporary deficiency, and thus worthily 
commemorate one so distinguished. 
' We regret that our limited space prevents the insertion of the full text of 
Professor Bonney’s Address, Thus the statement of facts relating to the Drifts of 
Britain have been omitted, but the main arguments relating to the interpretation 
of the phenomena have been retained. 
