OTHER TYPES OF APPARATUS 519 



structed by H. Murschhauser, 7 H. B. Williams 8 and F* 

 Tangl.* 



Studies of the gas exchange of aquatic animals require a 

 special technic, elaborated for observations on fish by 

 Zuntz, in association with Knauthe and Cronheim, 10 for 

 lower marine organisms by Jolyet and Regnard and by 

 Vernon. 11 



In conclusion the writer must not neglect to refer to the 

 great importance of Rubner's calorimeter in the develop- 

 ment of metabolic study; this relatively simple apparatus 

 must be credited, too, with a number of very important dis- 

 coveries, which may be offered as proof that in physiology 

 often far more is attained through judicious proposals of 

 problems and precise and skillful performance of work 

 than by elaborate and costly apparatus. 12 On the other hand 

 the study of metabolism itself teaches us that without a cer- 

 tain minimum of auxiliary means and power and the nervus 

 rerum requisite for procuring them, even the best arrange- 

 ment of researches must remain without result and the most 

 industrious hands without a task. The prime point in the 

 mechanical theory of heat, which has been occasionally cited 

 in these lectures in its popular rendering ("from nothing, 

 nothing comes ") , is applicable as well in the modern study of 

 metabolism. Just here the old hemisphere can learn much 

 from the new. Yet if unfortunately we are unable to bring 

 into existence a Carnegie Institution or a Rockefeller Insti- 

 tute, a very great deal can, nevertheless, be done in biochem- 

 istry with more modest means. 



7 H. Murschhauser (Acad. Pediatric Clinic, Diisseldorf ), Biochem. Zeitschr., 

 42, 262, 1912. 



8 H. B. Williams (Cornell Univ., New York), Jour, of Biol. Chem., 12, 

 317, 1912. 



9 F. Tangl (Budapesth), Biochem. Zeitschr., 44, 235, 1912. 



10 W. Cronheim, Zeitschr. f. Fischerei, 15, 319, 1911; separate pub. by Born- 

 trager Brothers, Berlin. 



"Literature on Respiration of Aquatic Animals: O. v. Fiirth, Vergl. chem. 

 Physiol. der niederen Tiere, pp. 121-130, Jena, 1903. 



12 0. Cohnheim, 1. c., p. 363. 



