BODY TEMPERATURE OF EARTHWORM. 



26.S 



one of the wires in a finely drawn glass tube, allowing the end of 

 the wire to extend slightly below the end of the tube, where it 

 was twisted together with the other wire of the couple. The 

 small glass tube with the two wires was then placed inside another 

 glass tube of a diameter just sufficient to receive them easily. 

 The glass of the outer tube was then sealed over the junction of 

 the wires, and the whole bent into a convenient form for handling. 

 The upper open ends of the tubes were sealed with wax to prevent 

 the access of any water and the apparatus was ready for use. 



FIG. i. Diagrammatic scheme of thermocouple. G = galvanometer; 

 cu = copper wire; con = constantan wire; j = junction. 



The galvanometer used in this work w r as one of the D'Arsonval 

 type made by Gaertner. It was provided with a dead beat coil, 

 and was so heavily damped that it was found desirable to allow 

 two or three minutes for the galvanometer mirror to come to 

 rest when making observations. It was found that with the 

 scale at about I meter distance i C. difference in the temperature 

 of the two junctions of the thermo-couple was represented by a 

 shifting of the reading of the galvanometer scale by about 16 

 millimeters. The actual amount of shift varied somewhat from 

 day to day from this value, and was re-determined for each 

 day's work. 



The technic of determining the temperature of the interior of 



