266 



CHARLES G. ROGERS AND ELSIE M. LEWIS. 



the worm was very simple. It consisted in placing the glass- 

 covered junction of the thermocouple in the mouth of the worm, 



and carefully pushing it down through the 

 oesophagus, crop and gizzard until it came to 

 lie in the stomach intestine. The other junc- 

 tion of the couple was placed in water of a 

 known temperature, and the two end wires 

 of the thermocouple were attached to the 

 galvanometer. The temperature of the water 

 in which the free junction of the thermo- 

 couple was placed was determined by a Beck- 

 man thermometer which had been set to a 

 definite reading by the side of a certified 

 standard thermometer. The temperature of 

 the water was determined to 1/100 C., and 

 was noted for every observation so that in 

 case of any variation in the temperature of 

 the water we should be able to make the neces- 

 sary correction in the results. The tempera- 

 ture of the worm was shown by the amount 

 of the deviation of the galvanometer read- 

 ing, from the zero reading, divided by the 

 number of millimeters representing i C., and 

 adding this amount to the known temperature 

 of the water. In this way we were able to 

 make readings which could be accepted as ac- 

 curate to within 0.03 C., which for our pur- 

 pose seemed to be sufficient. 



The following table gives data derived from 

 three experiments to show how closely and 

 how rapidly the temperature of the worm 

 becomes adjusted to the temperature of the 

 water in which it is immersed. We have not 

 thought it necessary to multiply examples as 

 all the facts observed are in perfect harmony 

 with those offered. In the experiments here cited both the worm 

 and the free junction of the couple were placed in the same bath. 

 The difference between the zero and in-circuit readings of the 



J 



FIG. 2. Sketch 

 of thermo-electric 

 clinical thermometer 

 for use with the 

 earth - worm, cu = 

 copper wire; con - 

 constantan wire ; j = 

 junction. 



