TABLE OF CONTENTS. 



PAGE 



- XXVII. On the Viscosity or Internal Friction of Air and other Gases (The 



Bakerian Lecture) 1 



- XXVIII. On the Dynamical Theory of Oases 26 



XXIX. On the Theory of tlie Maintenance of Electric Currents by Mechanical 



Work without the use of Permanent Magnets . . . . . 79 



XXX. On the Equilibrium of a Spherical Envelope ...... 86 



XXXI. On the best Arrangement for producing a Pure Spectrum on a Screen . 96 



XXXII. The Construction of Stereograms of Surfaces . . . . . .101 



XXXIII. On Reciprocal Diagrams in Space and their relation to Airy's Function of 



Stress . 102 



XXXIV. On Governors . . . . . . . . . . . .105 



XXXV. "Experiment in Magneto- Electric Induction" (in a letter to W. R. Grove, 



F.R.S.) ... 121 



XXXVI. On a Method of Making a Direct Comparison of Electrostatic with Electro- 



magnetic Force; with a Note on the Electromagnetic Theory of Light . 125 



XXXVII. On the Cyclide * 144 



XXXVIII. On a Bow seen on the Surface of Ice . . . . . . . .160 



XXXIX. On Reciprocal Figures, Frames, and Diagrams of Forces .... 161 



XL. On the Displacement in a Case of Fluid Motion ...... 208 



XLI. Address to the Mathematical and Physical Sections of the British Associa- 

 tion (1870) 215 - 



XLII. On Colour-Vision at different points of the Retina ..... 230 



XLIII. On Hills and Dales 233 



XLIV. Introductory Lecture on Experimental Physics ...... 241 



XLV. On the Solution of Electrical Problems by the Transformation of Conjugate 



Functions ............ 256 



XL VI. On the Mathematical Classification of Physical Quantities .... 257 



XLVII. On Colour Vision 267 



XLVIII. On the Geometrical Mean Distance of Two Figures on a Plane . . . 280 

 XLIX. On the Induction of Electric Currents in an Infinite Plane Sheet of 



uniform Conductivity 286 



