586 INDEX 



Skin, hot and cold spots, 390 ; irradiation, 398 ; pressure spots, 

 393. 



Smooth muscle, 356. 



Solution, gas in liquid, 16; normal, 165; solid in liquid, 16 j 

 tension, 16. 



Spectrum, 413, 432. 



Sphygmograph, 527. 



Spinal cord, localization of movements at different levels, 387 ; 

 destruction changes distribution of blood, 571. 



Spinal nerve roots, 386; sensory nerves, 388. 



Spontaneous contractions, 356. 



Staircase contraction, heart, 531. 



Stannius ligature, 562. 



Stimulation, 9; angle of current lines, 157; chemical, 163, 164; 

 constant, may cause periodic contraction, 165; demarcation 

 current, 290, 296; distilled water, 163; drying, 164; form 

 of muscle, 10, 156; induction current, 158; intensity changes, 

 99; mechanical, 166; minimal and maximal, 175; monopo- 

 lar, 111; polar, in heart, 110; summation of impulses, 176; 

 threshold value, 1 74 ; unipolar, errors, 320. 



Stroboscopic method, 305. 



Surface, caustic, 427, 428, 429; principal, crystalline lens, 

 418; principal, eye, 449. 



Surface tension, 25, 36. 



Summation of stimuli, 176. 



Superposition in tetanus, 347. 



Superposition of two contractions, 346. 



Sympathetic, action on heart, 556 ; frog, 556 ; preparation, 

 5o5. 



Synchronous points, method of obtaining, 120. 



System A, schematic eye, 440 ; B, schematic eye, 445 ; C, 

 schematic eye, 451. 



TEMPERATURE, hourly variation, 285 ; mouth, affected by food, 

 285; reaction to variations in, 285 ; regional, 285. 



Tension indicator, 25. 



Tetanus, 69, 346 ; electrical phenomena, 305 ; natural and arti- 

 ficial, 355 ; opening and closing, 147 ; Hitter's, 149. 



Threshold value of stimulation, 175. 



Tonus of heart muscle, 537. 



Tradescantia discolor, 20. 



Tuning fork, 88. 



UNIPOLAR induction, 71, stimulation, errors, 320. 



VAN DER WAAL'S hypothesis, 14. 

 Van't Hoff 's discoveries, 20. 



