22 



INJURY, EECOVERY, AND DEATH 



placed in a centrifuge tube near the bottom of which 

 platinum electrodes were inserted (through the walls of 

 the tube) a short distance apart. The material was then 

 centrifugated and the resistance was measured. The 

 supernatant liquid was then poured off and replaced by 

 a different solution. The material was agitated in order 



FIG. 1. Apparatus for measuring 

 the electrical conductivity of muscle 

 (Kodis) : E, electrode, contained in a 

 funnel (tilled with a solution of 

 NaCl) plugged at the bottom with 

 plaster of Paris CP); M, muscle: the 

 whole is placed in a water bath, I. 



to disperse it through the solution and the process of 

 centrifugation and washing was repeated until the first 

 solution was removed. This must be done frequently 

 since otherwise the organism may change the conduc- 

 tivity of the external solution (by absorbing or giving 

 out electrolytes) and this may be confused with a change 

 in the conductivity of the cells. 



A method of measuring the electrical conductivity 

 of bacteria has recently been proposed by Thornton 

 (1912), who states that it depends upon the principle 

 that in an electric field bacteria orient themselves in a 



