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Modern Electrical Theory 



By Norman Robert Campbell, Sc.D., Honorary Fellow for 

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Conduction of Electricity through Gases 



By Sir J. J. Thomson, O.M., F.R.S. (Second edition, enlarged 

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Elements of the flathematical Theory of Electricity 



and Magnetism 



By Sir J. J. Thomson, O.M., F.R.S. (4th edition.) $2.60 net. 



Sound 



An Elementary Text-book for Schools and Colleges 



By J. W. Capstick, M.A. (Camb.), D.Sc. (Vict.), Fellow of 

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Architectural and Building Construction Plates 



Part 1 . Thirty drawings covering an elementary course for archi- 

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" i quaring the Circle " 



A History of the Problem 



By E. W. HoBSON, Sc.D., L,L,D., F.R.S., Sadleirian Professor 

 of Pure Mathematics and Fellow of Christ's College, in the Uni- 

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A Geometry for Schools i 



By F. W. Sanderson, M.A., Headmaster of Oundle School and 

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