2712 



Journal of Applied Microscopy 



Klug, Ferd. Zwei Froschherz-Manometer als Prof. Klug has devised and describes 



Kreislaufschema und Versuche mit densel- j i.u u *.-*.i 



ben. Arch. f. d. ges. Physiol., 99: 594-6.8, ""^er the above title some very ingen- 

 1903. ious devices for demonstrating and 



studying the action of the heart under varying conditions. The simplest, and 

 perhaps most generally useful of these pieces of apparatus is shown diagram- 

 matically in Fig. 1. The different parts are mounted on a glass plate as abase. 

 Two metal cannulae of different sizes are passed through a rubber stopper (a). 



The larger of these cannulas is inserted and tied into the sinus venosus of a 

 surviving frog heart. The smaller cannulae is inserted in the left aorta. All the 

 other vessels of the heart are ligatured and the heart is removed from the body. 

 The heart so prepared is then suspended in a glass vessel containing .6 per cent. 

 NaCl solution, the vessel being closed above by the rubber stopper. From the 

 lower portion of this vessel passes a volumetric tube (d) by means of which the 



