220 



Dr. A. D. "Waller. 



Bibliography, 



1. Chauveau. " Utilisation de la tension electroscopique, &c." Congres de Lyon, 



1873. 



2. Boudet. ' ^lectricite medicale.' Paris, 1880. 



3. Marey. ' Methode graphique.' 



4. Dubois (Bern). ' TJntersuclmngen u. d. physiologische Wirkung des Conden- 



satorentladungen.' Bern, 1888; 



5. Dubois (Bern). " Recherches sur Taction physiologique des courants et 



decharges electriques." ' Arcliives des Sciences Physiques et Naturelles.' 

 G-eneve, 1891. 



6. D'Arsonval. " Relations entre la forme de 1' excitation electrique et la reaction 



nevro-musculaire," ' Arcliives de Physiologie,' p. 246, 1889. 



7. D'Arsonval. "Rapport sur l'eiectro-physiologie," 'Arcliives de Physiologie,' 



1890, p. 156. 



8. Salomonsen. ' Ned. Tydschr. v. Geneeskunde,' 1891. . 



9. Cybulsky and Zanietowsky. " Nouvelle methode d' excitation electrique, &c." 



' Cbt. f. Physiologie,' vol. 6, 1892, p. 167. ' Bull, de l'Acad. des Sciences de 

 Cracovie,' Avril, 1891. 



10. Cybulsky and Zanietowsky. " Ueber die Anwendung des Condensators zur 



Reizung der Nerven, &c," ' Pfluger's Archiv,' vol. 56, 1894, p. 45. 



11. Hoorweg. " Ueber die elektrische Nervenerregung," ' Pfluger's Archiv,' 



vol 52, 1892, p. 87. 



12. Hoorweg. " Ueber die Kervenerregung durch Condensatorentladungen." 



' Pfluger's Archiv,' vol. 57, 1894, p. 427. 



13. Grotch and Macdonald. " Temperature and Excitability," ' Journal of Physi- 



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Addendum received February 10, 1899. 



Sensificcdory Stimuli. 



In the attempt to. determine a "characteristic" of various modes 

 of sensificatory stimulation, I encountered the doubt, and, therefore, 

 difficulty, inherent to all investigations where the experimental 

 criterion is a subjective one — by appreciation of minimal sensation. 

 This broad distinction was, however, clearly apparent, that whereas 

 for series of stimuli of motor nerves the minimum exciting energy 

 decreased to a minimum from which it rose again (diminishing voltage 

 and increasing capacity), the energy of sensory stimuli of increasing 

 duration decreased indefinitely towards a minimum value. Within 

 the limits to which my experiments extended, decrease of energy was 

 made up for by increase of its duration. 



Testing on the human subject for minimal felt effect, by looking for 

 minimum effective capacity at a series of given voltages, I found it 

 difficult to distinguish between apparently different qualities of 

 minimal sensation , In the case of cutaneous nerves, it was generally 

 impossible to say whether the smallest " something felt " was directly 

 cutaneous or directly subcutaneous, or indirectly subcutaneous, by 



