571 



compared a linear thermopile of this kind, consisliiig of30 eieniciils, 

 witli a Rubens pile. Their resistance is tiio same (3 — 5 olims), and in 

 the ease of equal surface (20 X 1 mm.) my thermopile exhibits a 

 sensitiveness some 20 Va smaller. This disadvantage, however, is aniplv 

 compensated for by its rapidity, wiiich is 4 times as great^). 



Thermopiles of this construction are manufactured by Messrs. 

 Kipp & Sons of Delft. 



Physiology. — " Eocperimenis on the atonical muscle." IJ. By Prof. 

 J. W. Langelaan. (Communicated by Prof. H. Zwaakdeimakeh. 



(This communication will not be published in these Proceedings). 



^) A rapid and sensitive galvanometer of low resistance, adapted for use in 

 combination with these lliermcpiks, has been described in the proceedings of the 

 meeting of Jmie 28, 1913, p. 149. 



(December 27. 1913). 



37 



Proceedings Royal Acad. Amsterdam. Vol. XVI. 



