MEMOIR of JOHN MICHELL 



M.A., B.D., F.R.S., Fellow of Queens' College, Cambridge, 1749, 

 Woodwardian Professor of Geology in the University, 1762 



SIR ARCHIBALD CEIKIE, O.M., K.C.B., D.C.L., D.Sc, F.R.S. 



Crown 8vo. 2s 6d net. 



"John Michell applied his high intellectual powers to geological questions, 

 and, working without the key subsequently provided in the discovery of 

 fossiliferous deposits, forecasted many of the conclusions established by later 

 researches. In physics and astronomy he was the pioneer in devising the 

 torsion balance, which yielded such important results in the hands of Coulomb 

 and Cavendish. Though he enjoyed the esteem and respect of the most 

 eminent men of science in his lifetime, his name, mainly because others 

 entered into his labours and carried them to their full fruition, fell later into 

 unmerited obscurity. The thanks of students of the scientific history of our 

 country are due to our veteran geologist for the compilation of this valuable 

 and interesting memoir." — The Glasgoic Herald 



Cambviboe lllnipersit\? Ipress 



FETTER LANE, LONDON. E.G. 4: C. F. CLAY, Manager 



METHODS IN PRACTICAL PETROLOGY 



Hints on the preparation and examination of Rock Slices. 

 HENRY B. MILNER, B.A., F.G.S., etc., and GERALD M. PART, B.A., F.G.S. etc. 



2s. 6d. net. Postage 4d. 



This volume is ilesisrned to meet the practical requirements of geologists, students, and 

 others who employ the microscope as an aid to the determination of minerals and rocks. 

 It contains detailed information on section cutting, preparation and examination of rock 

 [;')lices, together with many microchemical methods for the confirmation of certain 

 tiTiinerals difficult of recognition by optical means alone. A chapter is also devoted to 

 /ioaethods employed when dealing with comminuted material, and tables of useful 

 rnineralogical constants are distributed throughout the text. 



Cambridge : W. HEFFER & SONS, Ltd. 



Now Ready. 

 PAL/EONTOCRAPHiCAL SOCIETY, ' 1916. — Vol. LXX. £1 5s. net. 



Contents which can be ha,d sepa.rcg.tely : — 



WOODWARD (A. S.). The Fossil Fishes of the English Wealden and 



Purbeck Formations. Part II, pages 49-104, Plates XI-XX. 10s. net. 

 HAEMER (F. W.). The Pliocene MoUusca of Great Britain. Part III, 



pages 303-461, Plates XXXIII-XLIV. 12s. net. 

 SPENCER (W. K.). A Monograph of the British Palaeozoic Asterozoa. 



Part III, pages 109-168, Plates VI-XIII. 8s. net. 

 ELLES (G. L.) and WOOD (E. M. R.). A Monograph of British 



Graptolites. Part XI, pages a-vi, cxlix-clxxi, 527-539, title-pages and 



index. 2s. Qd. net. 



