336 
the symmetric equatorial plane it is everywhere directed parallel to 
the z-axis. The most general case of any arbitrary point in the 
field leads to an expression for #, (a, y\, capable of integration but 
more complicated still than (7*). By differentiation 0./dy may also 
be obtained, though this also turns out rather intricate. In much the 
same way the distribution of $, along the z-axis may be calculated 
for prisms of finite length and the integrals. 
za za 
i §,(z)\dz and | ?,(z)dz 
al 1 
may be computed, of which the latter is of importance e.g. in the 
study of transverse magnetic birefringency. The case of an air-space 
shaped like a cylindric lens is of less practical importance and 
may here be omitted. 
Physiology. — “Influence of some inorganic salts on the action of 
the lipase of the pancreas.” (By Prof. Dr. C. A. PEKELHARING.) 
Hydrolytie fat-splitting by the lipase of the pancreas, the only 
enzyme that will be considered here, may be aided by a number 
of inorganic salts as well as by bile acids. It does not follow however 
that this action is always due to the same cause, to the process of 
activating the enzyme. 
It has been proved by Racurorp as early as 1891 that bile aids 
the action of the lipase of the pancreas especially on account of the 
presence of bile salts. The fat-splitting power of rabbit’s pancreatic 
juice was increased by the addition of a solution of glycocholate of 
soda nearly as much as by the addition of bile*). According to the 
researches of more recent investigators, especially TerrorNe*), it is 
highly probable, that the action of bile acids is based on a direct 
influence on the enzyme, so that here we might speak of an “activator” 
in the real sense of the word. The fact that various electrolytes also 
aid the hydrolysis of fat by the lipase, has been demonstrated by 
Porrrvin*) and more in detail by Terroir“); afterwards also 
by Minami‘). However, the mode of action of the electrolytes is still 
unknown, as has been clearly pointed out by Trrromn. The investi- 
gators I mentioned used for their experiments pancreatic juice or a 
1) Journ. of Physiol. Vol. XIL. p. 88. 
*) Biochem. Zeitschr. Bd. XXIII. S. 457. 
3) Compt. rend. Acad. d. Sciences, T. CXXXVI, p. 767. 
4) 1. c. S. 440. 
5) Bioch. Zeitschr, Bd. XXXIX, S. 392. 
