and Laboratory Methods. 



2293 



Fig. 2. 



lathe to a circumference of 50 cms. The weight is 600 grams. The drum is 

 borne on a brass sleeve which revolves about a steel shaft. The sleeve and 

 drum may be disconnected from the clockwork and then may be " spun " by 

 hand. 



The improved rheochord is in form of a square, as shown in Fig. 2. Its base 

 is a block of hard maple, 12.5 cms. square, upon which is placed a centimeter 

 scale beginning at the post shown on the left side of the figure and ending in 

 the 1-meter post visible in the background to the left. Along the scale, between 

 these two posts, is stretched the first meter of a continuous German silver wire, .2(3 

 mm. in diameter and 20 meters long. The remaining 19 meters of this wire are 

 coiled upon a spool, and the free end is 

 fastened to the 20-meter post shown in the 

 background to the right of Fig. 2. The 

 resistance in the 20 meters of German silver 

 wire is so great (about 184 ohms) that the 

 internal resistance of the element furnish- 

 ing the electromotive force, together wiih 

 the resistance of the large copper connect- 

 ing wires, practically disappears for ordi- 

 nary measurements. As the fall of poten- 

 tial is uniform throughout the 20 meters, 

 the difference of potential between post <» 

 and post 1 will be practically ^\y the electromotive force of the element. By 

 moving the contact block from post 1 toward post 0, any desired fraction of 

 this ^^ may be secured. The under surface of the contact block is bevelled 

 so that the metal touches the wire only with one edge ; the opposite edge is 

 supported by a piece of hard rubber, A flexible cable leads from the contact 

 block to the binding posts shown in the foreground to the right. 



These pieces of apparatus are manufactured for the Harvard physiological 

 laboratory under Dr. Porter's direction. They may be obtained through him at 

 very reasonable prices. r. p. 



Popielski, L, Ueber die Zweckmiissigkeit in The well known theory of Pawlow's 



der Arbeit der Verdauungsdiiisen. Kurz- , it • i i r 



gefasste Kritik der Verdauungslehre des that the digestive glands function in a 



Herrn Prof. J. Pawlow. Deutsch. Med. purposive way, adapting the secretion 



Wohnschr. No. 48, IQ02. , . , , • ■, r r 1 1 • 1 ■ 



to the particular kind of food which is 

 to be digested is strongly criticized by Popielski. The paper deals more partic- 

 ularly with the functioning of the pancreas, where this purposiveness is supposed 

 to be shown in the most pronounced manner. From results of his own work 

 and from results obtained in Pawlow's own laboratory Popielski shows that this 

 gland does not act in accordance with the " purposive " theory. An example 

 will indicate the sort of evidence which is brought forward in opposition to the 

 theory. It is found that a food mass made up of spleen, which contains no 

 amylaceous substances calls forth a secretion from the pancreas with a higher 

 content of diastatic ferment than that produced by feeding bread. Similar ob- 

 servations for other digestive glands are recorded. R, P. 



