CONTENTS. 
PART I. 
I. On the Bodily Tides of Viscous and Semi-elastic Spheroids, and on the Ocean Tides 
upon a Yielding Nucleus. By G. H. Darwin, M.A., Fellow of Trinity College, 
Cambridge. Communicated by J. W. L. Glaisher, M.A., F.R.S.. . page 1 
II. On the Spectra of Metalloids—Spectrum of Oxygen. By Arthur Schuster, 
Ph.D., F.R.A.S. Communicated by J. Clerk Maxwell, F.R.S., Professor of 
Experimental Physics in the University of Cambridge ....... 37 
III. Electrodynamic Qualities of Metals. —Part VII. Effects of Stress on the Magneti¬ 
zation of Iron , Nickel, and Cobalt. By Professor Sir William Thomson, 
F.R.S. ....55 
IV. On Repulsion resulting from Radiation. —Part VI. By William Crookes, 
F.R.S., V.P.C.S. . .. . 87 
V. The Bakerian Lecture .—On the Illumination of Lines of Molecular Pressure, 
and the Trajectory of Molecules. By William Crookes, F.R.S., V.P.C.S. 135 
VI. On the Sensitive State of Electrical Discharges through Rarefied Gases. By 
William Spottiswoode, D.C.L., LL.D., Pres. R.S., and J. Fletcher 
Moulton, late Fellow of Christ’s College, Cambridge .165 
VII. On Stresses in Rarified Gases arising from Inequalities of Temperature. By 
J. Clerk Maxwell, F.R.S., Professor of Experimental Physics in the Univer¬ 
sity of Cambridge ...231 
VIII. Researches on the Action of Organic Substances on the Ultra-violet Rays of 
the Spectrum. By W. N. Hartley, F. Inst. Chem., F.R.S.E., F.C.S., 
Demonstrator of Chemistry, King’s College, London; and A. K. Huntington, 
F. Inst. Chem., A.R.S.M., F.C.S . Communicated by Professor G. G. Stokes, 
Sec. R.S. .. 257 
IX. On the Microrheometer. By J. B. Hannay, F.R.S.E., F.C.S., lately Assistant 
Lecturer on Chemistry in the Owens College, Manchester. Communicated 
by H. E. Boscoe, Ph.D., Professor of Chemistry in Owens College, 
Manchester .....275 
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