252 



A. I. RINGER AND ElllL J. BAUMANN 



sent the arrangement by an inclined tube that has a series of outlets at 

 different levels, with openings at the bottom through which sugar may bo 

 pumped in. The level of sugar in this inclined tube will depend upon 

 the speed with which it is pumped in and with which it pours out at the 

 various outlets. If the inflow is so rapid that the first outlet cannot take 

 care of it all, it will mount until it reaches the second. If that is not 

 sufficient, it will reach the third, and if that is not sufficient, it will mount 

 still higher. 



Uvel *<D uTuLer Contrd ofPancrwtk Hormone. 



Regulated by RenaiThrssholi. 



Fig. 2. Schematic illustration of the factors which regulate the sugar concentra- 

 tion of* the blood. 



The level of sugar in this tube at any given time will depend upon the 

 relationship between the velocity and volume of the sugar inflow at the 

 bottom, and the volume and velocity of its outflow through the three 

 normal channels. 



In the body, the glucose concentration of the blood at any given time 

 also depends upon the speed and amount of its absorption from the in- 

 testinal canal, and upon the speed of its removal by utilization, glycogen 

 and fat formations. Normally it seldom goes above 0,12 or 0.13 per 

 cent, because the glycogen formation proceeds at such a rapid pace that 

 it does not permit its accumulation in the blood. When we ingest carbo- 

 hydrates in the form of starch, we can take absolutely unlimited quantities. 

 Because the digestion of it is rather slow, the absorption follows suit, and 



