124 



APPENDIX 



of various samples of egg-albumin containing from 89 to 90 per cent, 

 of water of from 340 to 400 ohms per cubic centimetre at 20 C. to 15 C. 

 Within the range of temperature given, the source of the sample of albumin 

 affects the conductivity more than the temperature does. A sample from 



FIG. 16. Diagram of apparatus for finding the conductivity of egg-albumin by the differential method. G = gal- 

 vanometer ; S, ^ = switch-keys ; R = resistance-box ; B = battery ; Pt = platinum-electrodes, insulated on back 

 and on wire with shellac. 



a new-laid egg, for example, had a lower conductivity at 20 C. than that 

 from an older one at 15 C., although in all cases the conductivity of the 

 same sample of egg-albumin increases as the temperature rises. This 

 applies even when the temperatures are such as to produce coagulation ; 

 and, in fact, the conductivity may be two-and-a-half times as great at 

 85 C. as it is at i8C. 



In illustration of this, the results of the following two experiments 

 are appended : 



Temperature. 



A. Egg-albumin containing 89 per cent, of water. i8C. 



Coagulated at 90 C. and cooled to 85 

 > ii 1 8 



B. Egg-albumin containing 90 per cent, of water. 16 



Coagulated at 85 C. and cooled to 80 

 40 



20 

 15 



Resistance in 

 ohms per c. c. 



4 l6 

 188 

 4 l6 



501 



235 

 4 00 



485 

 510 



