THE CHEMISTRY OF LIGHT PRODUCTION 97 



thermo-couple on the galvanometer scale were therefore 

 taken at one-minute intervals for some time before and 

 after mixing the luciferin and luciferase solutions and 

 plotted as curves. Control experiments were also carried 

 out in exactly the same manner as the luciferin-lucif erase 

 experiments, but water was placed in the two tubes instead 

 Q) 



o 



O 

 > 





0> 



o 



28.5 



28.0 



«s > 

 Id "d 



^ 27.5 



340 



Time 



m 



3.50 4.00P.M. 



minute-s 



Fig. 35. — Curve showing temperature change when luciferin and luciferase solutions 

 at the same temperature are mixed. 0.1 galvanometer scale division = 0.003° C. Dots 

 represent readings of thermooouple in luciferin solution; crosses, readings of thermocouple 

 in luciferase solution. 



of luciferin and luciferase. Figs. 34 and 35 give typical 

 experiments with water and with luminescent solu- 

 tions, respectively. 



With both control (water) and luciferin experiments 

 there was a slight rise in temperature on mixing the liquids 

 in the two tubes. The average rise of five control (water) 

 experiments was .0054° C. and the average rise of five 

 luciferin experiments was .0048° C. 



