INDEX 
TO THE 
PHILOSOPHICAL TRANSACTIONS 
FOE THE YEAE 1877. 
A. 
Absorption-spectra of two similarly coloured and allied gases compared, 207 (see Roscoe). 
Adams (W. G.) and Day (R. E.). The Action of Light on Selenium, 313. — Effect of moonlight on 
selenium, 315 ; the change in resistance is as the square of the illuminating power, 318 ; resistance 
altered by changing the intensity or direction of the current, 323 ; polarization produced by the 
current, 328 ; Appendix, the place of selenium in the thermoelectric scale, 342 ; selenium changed 
in character by the action of time, 348. 
Amblystoma, skull of, 529 (see Parker) . 
Axolotl, development of the skull of, 529 (see Parker). 
B. 
Bacteria, resistance of, to destructive agents, 149 (see Tyndall). 
Batrachian skull, 529 (see Parker). 
Brodie (Sir B. C.). The Calculus of Chemical Operations; being a method for the investigation, by 
means of symbols, of the laws of distribution of weight in chemical change. — Part II., on the Ana- 
lysis of Chemical Events, 35 (for Contents see p. 35). 
Bromine, absorption-spectrum of vapour of, compared with that of iodine monochloride, 207 (see 
Roscoe) . 
Brunton (T. L.) and Pye (W.). On the Physiological Action of the Bark of Erythrophleum guinense , 
generally called Casca, Cassa, or Sassy Bark, 627. 
C. 
Casca Bark, physiological action of, 627 (see Brunton) . 
Casey (J.). On a new Form of Tangential Equation, 367. — Introduction, 367 ; transformation of 
tangential into Cartesian equations, 377 ; into intrinsic, 379 ; of intrinsic into tangential, 383 ; 
involutes, 393 ; positive pedals, 397 ; negative pedals, 399 ; the cycloid, 406 ; intern and extern 
cycloids, 410; if two tangents to a cycloid intersect at a constant angle, the locus of their point of 
intersection is an extern cycloid, 414 ; epicycloids, 415 ; the hypocycloid, 420 ; extern epicycloids, 
421; parallel curves, 425. 
MDCCCLXXVII. 5 O 
