190 BULLETIN PHILOSOPHICAL SOCIETY OF WASHINGTON. 
Page 
Harmony 172 
Helium, Discovery of 41 
— evolved from cleavite 41 
Hertzian diagram 50 
Hildebrandsson, charts of, 1895 46 
Hydrodynamics 49, 51 
Hydrostatic equilibrium 63 
— pressure 60 
Hygrometer, catgut, used by Brander, 
1650 39 
— hair, used by De Saussure, 1780.. 39 
Indian monsoons 45 
“Instruments and methods of re- 
search,” by L. A. Bauer 103 
“International Meteorological Obser- 
vations, Weather Bureau Bulle- 
tin A, Summary of” 46 
Invisible spectrum 89 
Ionization of atmospheric gases 42 
Isostasy, Theory of 64 
Kinetic relations of winds to storms. 38 
Kirchhoff's solar theory 79 
Kites used in study of meteorology. . 46 
Krypton, Discovery of 41 
Kummer’s theory of curved light rays 93 
Lamp black 80 
Langley, S. P., Obituary notice of, by 
C. Adler 1 
Light, Absorption and emission of . . . 78 
— Pressure of 85 
Lindenberg Observatory 47 
Magnetic survey of Pacific and At- 
lantic oceans 123 
the globe 124 
Magnetism, Terrestrial 116 
Mathematical theory of heat 48 
Maxwell’s theory of radiation 85 
Mechanical properties of air 34 
Mechanics of the atmosphere 42 
earth’s atmosphere 28 
Meteograph, Use of 47 
Meteorological offices of France and 
Germany 30 
— Society of the Palatinate at 
Mannheim 36 
— stations established in Italy 36 
Meteorology 116 
— a distinct science 28 
— Elementary 32 
Mirage and twinkling of stars 33 
Monsoon currents 43 
Mountain stations 46 
— observatories established 46 
Page 
Mount Weather Observatory 56 
“Music and Science,” by C. K. Wead. 169 
Musical scales 172 
National Meteorological organizations 30 
Neon, Discovery of 41 
Neptune, Curved light x*ays on 93 
Newcomb, Simon, Memorial addresses 
on, by C. K. Wead, James Bryce, 
Milton Updegraff, R. S. Wood- 
ward, L. O. Howard, Herbert 
Putnam, and E. M. Gailaudet. 
Resolutions read by O. H. Titt- 
mann 133 
Nitrogen, Discovery of, in 1772 by 
Rutherford 40 
— thermometers 84 
“On the stresses caused in the in- 
terior of the earth by the weight 
of continents and mountains,” by 
G. II. Darwin 59 
“On the temperature and structure of 
the sun,” by O. Lumraer 75 
Opthalmoscope 77 
Oxidation of air 39 
Oxygen, Discovery of, by Priestley 
and Scheele 40 
Pendulum observations 64 
Photosphere 93 
“Physical dissertation on the sudden 
variations observed in atmos- 
pheric pressure,” by Prof. H. W. 
Brandes 36 
— properties of air 34 
Platinum black * 80 
Polonium, Discovery of, by Madame 
Curie, 1898 41 
Polyphony 172 
“Progress of Science as illustrated 
by the development of Meteo- 
rology,” by C. Abbe 27 
Properties of the atmosphere, Consti- 
tution and 38 
Psych rometer used by Baume and 
others 39 
— Whirled 39 
Radium, discovered by Madame Curie, 
1898 41 
Rainbow, Explanation of the 33 
Refractive power of the atmosphere. . 33 
“Reminiscences of an astronomer,” 
by Simon Newcomb 103, 145 
Respiration of air 30 
Roentgen X-rays 79 
