LIST OF FIGURES. 



FIG. 



1. A muscle-nerve preparation ......... 56 



2. Diagram of du Bois-Reymond key ........ 58 



3. Diagram illustrating apparatus arranged for experiments with muscle 



and nerve ............ 60 



4. Diagram of an induction coil ......... 62 



5. The magnetic interrupter ......... 63 



6. The magnetic interrupter with Helmholtz's arrangement for equaliz- 



ing the make and break shocks ........ 64 



7. A muscle-curve from the gastrocnemius of a frog ..... 66 



8. The same, with the recording surface moving slowly .... 66 



9. The same, with the recording surface travelling very rapidly . . 67 



10. The pendulum myograph ......... 68 



11. Diagram of an arrangement of a vibrating tuning-fork with a Desprez 



signal ............. 70 



12. Curves illustrating the measurement of the velocity of a nervous impulse 73 



13. Tracing of a double muscle-curve . ... C ... 76 



14. Muscle-curve. Single induction-shocks repeated slowly ... 76 



15. The same, repeated more rapidly ........ 77 



16. The same, repeated still more rapidly ....... 77 



17. Tetanus produced with the ordinary magnetic interrupter ... 78 



18. Non-polarizable electrodes ......... 98 



19. Diagram illustrating the electric currents of nerve and muscle . . 99 



20. Diagram illustrative of the progression of electric changes . . . 103 



21. Diagram of ascending and descending constant current . . .112 



22. Diagram of the electro tonic changes in irritability . . . .114 



23. Diagram illustrating electrotonic currents ...... 115 



24. Scheme of the nerves of a segment of the spinal cord .... 140 



25. Apparatus for investigating blood pressure ...... 157 



26. Tracing of arterial pressure in dog ..... ... 158 



27. Tracing of arterial pressure in rabbit ....... 159 



28. Lud wig's kymograph .......... 160 



29. Diagram of fall of blood pressure in arteries, capillaries and veins . 161 



30. Arterial scheme ........... 167 



31. Tracing from arterial model with little peripheral resistance . . 168 



32. The same with increased peripheral resistance ..... 169 



33. Ludwig'sstromuhr ........... 173 



34. Chauveau and Lortet's hsematachometer ...... 174 



35. Diagram illustrating causes determining the velocity of the flow . . 176 



36. Tracing from heart of cat ......... 186 



xliv 



