44 CHARLES GRIFFIN & CO. VST PUBLICATIONS. 



By PROFESSORS J. H. POYNTING & J. J. THOMSON. 



In Large 8vo. Fully Illustrated. 



A TEXT-BOOK OF PHYSICS: 



COMPRISING 



PROPERTIES OF MATTER; SOUND; HEAT; MAGNETISM 

 AND ELECTRICITY; AND LIGHT. 



BY 



J. H. POYNTING, J. J. THOMSON, 



8C.D., F.R.S., A ir D M.A., F.K.8., 



L*te Fellow of Trinity College, Cambridge; Fellow of Trinity College, Cambridge; Prof. 



Professor of Physics, Mason College, of Experimental Physics in the Univanity 



Birmingham. of Cambridge. 



Volume I., Now Ready, Price 8s. 6d. 



SOU MD. 



Contents. The Nature of Sound and its chief Characteristics. The Velocity of Sound 

 in Air and other Media. Refl'C'ion and Refraction of Sound. Frequency and Pitch of 

 Notes. Resonance and Forced Oscillations. Analysis of Vibrations. Tiie Transverse 

 Vibrations of Stretched Strings or Wires. Pipes and other Air Cavities. Rods. Plates. 

 Membranes. Vibrations maintained by Heat. Sensitive Flames and Jets. Musical 

 Sand. The Superposition of Waves. Index. 



%* Publishers' Note. It is intended that this IMPORTANT and LONG-EXPECTED 

 TREATISE shall be issued in separate Volumes, each complete in itself, and 

 published at regular intervals. 



In large 8vo, with Bibliography, Illustrations in the Text, and seven 

 Lithographed Plates. I2s. 6d. 



THE MEAN DENSITY OF THE EARTH: 



An Essay to which the Adams Prize was adjudged in 1893 in 

 the University of Cambridge. 



BY 



J. H. POYNTING, Sc.D., F.R.S., 



L,ate Fellow of Trinity College, Cambridge; Professor of Physics, Mason 

 College, Birmingham. 



"An account of this subiect cannot fail to be of GREAT and GBKHBAL IHTHBHST to the scientlfle 

 >mind. Especially is this the case when the account, is given by one who has contributed o 

 considerably as has Prof. Pointing to our present state of knowledge with respect to a very 

 fltlfflcult subject. . . . Remarkably has Newton's estimate been verified by Prof. Poyuting." 

 Mhenaum. 



LONDON: CHARLES GRIFFIN & CO., LIMITED, EXETER STREET, STRAND. 



