SUBJECT INDEX 



371 



Iris, 109 



Iron arc, ultraviolet radiations from, 142 



Isodose curves, 48 



Isosmotic solutions, 193 



Isotonic coefficients, 196 



Isotonic solutions, 193, 194 



Keratoconus, 103 



Kuder photoelectric colorimeter, 156 



Ladd-Franklin color theory, 130 



Lambert, defined, 113 



Landolt's broken ring, 128 



Larvicide, 176 



Lattice constant of NaCl, 13, 14 



Lead equivalent, 37 



Lenticular opacities, 120 



Lenticular process, 273 



Lethal action of radiation on bacteria, 



160 

 Lillie's nerve propagation model, 228 

 Liquid surfaces, 170 

 Longitudinal waves, 256 

 Loudness, 292, 306 

 Loudness contours, 289, 295 

 Loudness function, 294 

 Loudness scale, 293 

 Low-intensity vision, 126 

 Lumen, defined, 113 



Magnification, by objective, 323 



table of eyepieces, 318, 319 

 Malleus, 263, 268, 302 

 Malleus-incus, articulation, 263, 268, 273 



coupling, 273 



mechanical advantage, 271 



transmissions, 273 

 Manubrium, 263, 268 

 Masking of sound, 295, 296, 307 

 Mass absorption coefficients, of hydro- 

 gen, 20 



of metals, 20, 21 



table of Cu, Al, H 2 0, 18 



of tissues, 20 

 Mechanical equivalent of fight, 115 

 Mel, defined, 297 

 Melanin, skin content, 137 

 Membranes, 170 



aural, 306 



Membranes, basilar, 277, 284, 285, 286, 

 305 



hypothesis, 170, 204-207 



permeability, 170, 187 



Reissner's, 282, 283, 284 



semi-permeable, 188, 189, 209 

 Mercury-vapor arc, 139 

 Microscope, compound, 311-330 



condenser for, 326 



diaphragm, 327 



electron, see Electron microscope 



magnifying power, 312 



mirror, use, 327 



structure, 313 



visible area, 330 



working aperture, 327 

 Middle ear, cavity of, 261, 262 



mechanism of, 267-282 

 Millibar, 198, 199 

 Millicurie, 76 

 Millicurie-hour, 79 

 Modiolus, 271, 282, 285 

 Molecular extinction coefficient, 147 

 Molybdenum, x-ray spectrum, 11 

 Monomolecular films, 205, 226 

 Monophasic action potential, 216, 219 



Nerve, accommodation, 225 



action potential, 216 



conduction, 211 



effects of anesthetics, 225 



excitatory process, 211, 230 



propagation theory, chemical, 230 

 physicomathematical, 229 

 pulse, 227 



velocity, 224 

 Nerve fibers, 214, 222 

 Nerve impulse frequency, 224 

 Nerve response, correlated with loud- 

 ness, 305 



correlated with pitch, 305 

 Nerve stimulus, 212, 230 

 Nerve structure, 214 

 Nerve trunk, action potential, 220 

 Nitella, membrane, 209 

 Nodal circles, 265 

 Non-polarizable electrodes, 214 

 Nethelometer, 150 



Numerical aperture, 312, 318, 325, 326, 

 349 



