viii CONTENTS OF VOL. IV. — FOURTH SERIES. 



Page 



M. H. Helmlioltz on the Theory of Compound Colours 519 



Mr. J. Newman's Description of a new Evaporating Gauge . . 534 

 Notices respecting New ISooks : — Mr. J. Farren's Life Contin- 

 gency Tables. — Part I. ; Mr. W. D. Snooke's Brief Astrono- 

 mical Tables for the Expeditious Calculation of Eclipses in 



all ages 535-538 



On a remarkable Deposit of Tin-ore at the Providence Mines 



near St. Ives, CornwaU. by W. J. Henwood, F.R.S., F.G.S. 538 

 On the Nature and Name of Ozone, by C. F. Schdnbein .... 542 

 On the Quantitative Determination of Ozone, byC.F. Schdnbein. 545 

 On the Motion of Fluids from the Positive to the Negative Pole 



of the closed Galvanic Circuit, by M. Wiedemann 546 



Index 548 



ERRATUM. 



Page 359, hue 7, for unchangeably reffc? unchangeable, and insert a comma. 



PLATES. 



I. and II. Illustrative of Dr. Barry's Paper on the Spiral Structure of 

 Muscle. 



HI. Illustrative of Dr. Anchews's Paper on a new Aspirator. 



IV. Illustrative of Dr. Tyndall's Paper on the Reduction of Temperature 

 by Electricity. 



V. Illustrative of Mr. Grove's Paper on the Electro-chemical Polarity of 

 Gases. 



