32 Robertson, Further Explanatory Remarks Concerning etc. 



den wirklichen abweichen." This statement contains two inaccuracies. 

 In the first place my interpretation of the autocatalytic formula is, 

 as we have seen, correct and identical with Moeser's while my 

 employment of it is accurate in principle and Moeser's is not. In 

 the second place in all cases in which I have stated that the 

 autocatalytic formula certainly applies the deviations between theory 

 and experiment never exceed 20/ and are in almost every instance 

 much less than this. This is especially true when the data are 

 derived from the average of a large number of individual measur- 

 ements. The large deviations to which Moeser refers occur in 

 cases to which, as 1 have expressly pointed out in each of the 

 articles to which I have referred, the autocatalytic formula 

 does not apply. In fact I refer to these deviations as direct 

 proof that the formula does not apply. It appears necessary once 

 more to reiterate my statement that the autocatalytic growth-formula 

 does not apply in the following instances: 



1. To the decrease of weight which occurs in senile decay, 

 from which Loeb 6 ) and I have argued that the processes underlying 

 senile decay are essentially different from those which underlie 

 growth. 



2. To the growth of the Mineral Content of plants. This 

 has recently been confirmed by Chodat and Monnier 2 ) who have 

 shown that it is due to the fact that at certain periods in the 

 growth of plants there is a negative Migration" of mineral constit- 

 uents from the plant into the soil. 



In passing I wish to correct yet a third mis-statement made 

 by Moeser. He asserts (p. 370), without citing any article, that I 

 have employed two autocatalytic curves to represent the complete 

 curve of muscular contraction, the one representing the ascending 

 portion of the curve, the other the descending portion of the curve. 

 I have never done so and in no publication have I attempted to 

 apply the autocatalytic formula to the curve of muscular contraction. 

 I have, it is true, ventured to assert that autocatalytic processes 

 underlie muscular contraction 7 ), but I cited, in support of this 

 view, not the form of the curve of muscular contraction, but the 

 fact that muscular contraction is rendered more energetic by 

 perfusing the muscle with a weak solution of the products of 

 muscular activity, and less energetic by perfusing it with a stronger 



5) J. Loeb. ,,Die cheruische Entwicklungserregung des tierischen Eies". 

 Berlin 1909, p. 246. 



6) R. Ohodat and A. Monnier. Arch. d. Sciences physiques et naturelles. 

 Soc. de physique et d'histoire naturelle de Geneve. 4 me Ser. tome 33, p. 101 (1912). 



7) T. Brailsford Robertson. "On the Biochemical Relationship between 

 the 'Staircase' phenomenon and Fatigue". Festband der Biochem. Zeitschr. f. 

 H. T. Hamburger, 1908, p. 287. 



