284 Sir John Lubbock’s Address. 
tained that such causes as those now in operation, would, if 
only time enough were allowed, account for the geological 
structure of the earth; nevertheless the opposite view generally 
prevailed, until Lyell, with rare sagacity and great eloquence, 
with a wealth of illustration and most powerful reasoning, con- 
vinced geologists that the forces now in action are powerful 
enough, if only time be given, to produce results quite as 
stupendous as those which Science records. 
_ As regards stratigraphical geology, at the time of the first 
meeting of the British Association at York, the strata between 
the carboniferous limestone and the chalk had been mainly 
reduced to order and classified, chiefly through the labors of’ 
William Smith. But the classification of all the strata lying 
above the chalk and below the carboniferous limestone respec- 
tively, remained in a state of the greatest confusion. The year 
1831 marks the period of the commencement of the joint labors 
of Sedgwick and Murchison, which resulted in the establish- 
ment of the Cambrian, Silurian, and Devonian systems. Our 
Pre-Cambrian strata have recently been divided by Hicks into 
four great groups of immense thickness, and implying, there- 
fore, a great lapse of time; but no fossils have yet been discov- 
ered in them. Liyell’s classification of the Tertiary deposits ; 
the result of the studies which he carried on with the assistance 
of Deshayes and others, was published in the third volume of 
the “Principles of Geology” in 1833. The establishment of 
Lyell’s divisions of Eocene, Miocene and Pliocene, was the 
starting-point of a most important series of investigations by 
Prestwich and others of these younger deposits; as well as 0 
the Post-tertiary, Quaternary, or drift beds, which are of special 
interest from the light they have thrown on the early history of 
man. 
A full and admirable account of what has recently been 
Before 1831 the only geological maps of this country were 
geologically, and a sum of 800i. was granted for the apd gat 
O i i of the 
. 
tain masses, were neither more nor less than parts of a gigantic 
