Hoyt and Fabula 



1^00 2,000 



CONCENTRATION, WPPM 



2,500 



Fig. 2 - Rotating-disk torque curves for guar additive 



150 200 250 300 350 400 450 500 550 600 650 

 CONCENTRATION, WPPM 



Fig. 3 - Rotating disk-torque curves for 

 poly(ethylene oxide) additives 



962 



