MEMOii;a UF THE ^'ATIO^^AL ACADEMY OF SCIENCES. 



413 



done and tlie part sn|ipnrted by siinjilc, devices. Tims tlie arm was placed comfortably in a padded 

 wooden box and tlie base of the liamiiicr could be swung around so that the blows could be given 

 successively on the lower and upper arm without moving thii arm. The iM)ints used were the back 

 of the lower and upper arm (E and /'', (jpposite the jwints /.' and />, tig. 7), at a, distance of .lO 

 cm., the lower and upper i)arts of the thigh {G and H, the front of the leg, but anaton'iically 

 corresponding to the back of the arm) at a distance of 25 cm., the back of the second joint of tlie 

 left forefinger (7 ) and of the left great toe (J), the cheek (A') belovv the zygoma about 2 cm. from 



the base of the concha of the ear, and the back of the necik (L) over the second spinal process. 

 Keactions wei-e also made with the hand and foot, the stimulus being applied on the forefinger. 

 The expernneuts were made in sets, U and F, G and H, I and J, K and i, and the inovement 

 with foot and hand, respectively, being made simultaneonsly. Experiments made simultaneously 

 and under the same conditions can be best compared, but our times were found to vary but little 

 from day to day. In these experiments the objective force of the blow was always the same 

 (a weight of 30 grams falling 20 em.). The reactions were measured singly, the variations of the 

 separate times from the average time of the series and of the separate series from the average 

 time of the set both being given. 



Table XI.— lieactioii-times on blows on various parts of the body. D, C, and J observers. 2,000 reactions. 



E.. 



F. 



G.. 



H.. 



I .. 



J.. 



K.. 



L.. 



I .. 



I .. 



D. 



Back of lower arm 



Back of upper arm 



FroDt of lower thigh 



Front of upper tbigli 



Back of second joint of forefinger. 

 Back of second joint of big toe... 



Clieek , 



Back of neck 



147.1 

 146.5 

 137.3 

 160.7 

 130.2 

 122.1 



11. t: 

 11.1 



10.5 

 13.0 

 10. S 

 9.7 



(0.2) 

 (S.S) 

 (6.6) 

 (4.9) 

 (7.4) 



115 



115.8 



121.4 



122.2 



105.5 



120.8 



103.1 



110.3 



Second joint of fnrefin<;er R with hand 106. 1 



6.9 



8 



7.S 



7.5 



e.6 



7.S 

 5.9 

 7.5 

 5.7 



(7.4) 

 (5.4) 

 (4. J) 

 (3.7) 

 {3.5) 

 (S.7) 

 (S.7) 

 (3.1) 

 (J. 5) 



Second joint of forefinger K with foi>t 1 168. 9 10.6 {5.S) 



J. 



113.3 

 114.7 



9.S 



9.S 



(6.3) 

 (4.3) 



110.6 7.S (» ) 

 147. 3 11 (J. 7) 



