242 Eminent Living Gleologists— 
transferred to Dr. Valpy’s at Reading, and finally entered University 
College, Gower Street, then just established. 
He was a diligent student under Dr. Turner and Dr. Lardner in 
the Chemical and Natural Philosophy Classes, somewhat to the 
neglect of his classical studies. 
‘At that time a student of geology had to be his own master and 
teacher. There was hardly a text-book and no public lectures, except 
three lectures on mineralogy and geology forming a part of the 
course of forty lectures by Dr. Turner on chemistry. The proximity 
of the British Museum he found of great advantage for the study of 
the geological and mineralogical collections between lectures. 
Whilst still a student at University College, he started a Society 
amongst young men of his own age (from 18 to 20), each of whom 
engaged in turn to deliver a lecture on Chemistry or some branch of 
Natural Philosophy. There were about fourteen members who met 
regularly in rooms in Surrey Street, Strand, where they had a small 
Laboratory, and styled themselves the “ Zetetical Society.” But by 
degrees, owing to professional and business engagements, the Society 
was broken up. 
Mr. Prestwich’s own tastes would have led him to adopt a 
profession, but circumstances caused him to enter into business in 
which he remained closely engaged until the year 1872. Ue was 
frequently in France and Belgium between 1836 and 1850, which 
gave him the opportunity of making the acquaintance of most of 
the French geologists, including Deshayes, Hébert, Chas. D’Orbigny, 
Lartet, D’Archiac, Desnoyers, Constant Prevost, Delesse, De Verneuil, 
Omalius d’Halloy, Dumont, de Koninck, and later on with Gaudry, 
Daubree, Belgrand, Gosselet, Nyst, Dupont, and others ; many last- 
ing friendships were thus established. 
Mr. Prestwich’s first paper was on the ‘“ Gamrie Ichthyolites,” to 
which the then scarcely known Hugh Miller, of Cromarty, had just 
divected attention. His holidays in 1831-32 were spent in the inves- 
tigation of the coal field of Coalbrook Dale, and his memoir thereon, 
with the description by his friend Professor Morris of various new 
species of plants and mollusca, showing the horizons to which each 
of them belonged, was published four years later in the Transactions 
of the Geological Society of London. 
This paper was followed by a series of others, printed in the 
Quarterly Journal of the same Society, on the structure and organic 
remains of the several groups of strata of the London and Hampshire 
Tertiary Basins. In these memoirs he established the existence, at 
the base of the known deposits, of a marine formation which he 
designated the “Thanet Sands,” proved the synchronism of the 
barren mottled and plastic clays of Reading with the fluvio-marine 
beds and fossiliferous pebbly sands of Woolwich; and showed that 
the London clay was not the equivalent of the Bracklesham and 
Barton beds, but that it occupied a lower zone, and was synchronous 
with the Bognor beds of the Hampshire Basin. 
This re-arrangement of the English Hocene series necessitated a 
revision of their correlation with the same strata in France and 
gli 
