XXIV. To determine the general influence of the vagus 

 nerve upon the circulation.* 



/. Appliances. Operating case, (Appendix, A-3); a pair 

 of curved, blunt-pointed shears, or better, a pair of 

 barber's clippers; a rabbit board; large sheet of heavy 

 paper; sealing wax; cotton; ether; thread; 1 Daniell 

 cell; inductorium; vagus electrodes; 2 Du Bois keys; 7 

 wires; stethoscope; a strong, adult rabbit. 

 2. Preparations. Let the six students be subdivided into 

 three groups of two students each. 



Let group "0" be responsible for the anaesthesia. 

 Use the sheet of heavy paper to make a conical hood, 

 whose spiral turns may be held in place with sealing 

 wax. Place a wad of cotton loosely in the mouth of 

 the cone. 



Let group "" perform the operation. Fix the rab- 

 bit, back downward, upon the holder; fix the nose in 

 special holder (see Fig. 19); with the barber's clippers 

 remove the hair from ventral side of thorax and neck ; 

 make hands and instruments clean, place instruments 

 in a shallow basin of warm, 1 per cent carbolic acid 

 solution; cut two or three ligatures of thread and 

 place them in the instrument basin. 



Let group " c " arrange the electrical apparatus for 

 stimulation of the nerves. Fill the cell; join up with 

 contact-key in the primary circuit, and a short-circuit- 

 ing key in the secondary circuit. Test the apparatus to 

 see if everything is in order, 

 j. Operation. 



Group "a." (1) Pour 2 cc. or 3 cc. of sulphuric 



*Let six students work together. 



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