lotka: an objective standard of value 



499 



The analytical figures do not express the relationships as 

 clearly as the molecular ratios which are therefore reproduced 

 below : 



Ratios of Muthmannite Analyses 



1 Includes 0.03 Pb. 



The ratio of Te to (Ag + Au) is 1 : 1 in all four analyses, and 

 the silver also predominates over the gold in all four analyses. 

 The mineral described as empressite is therefore a pure muth- 

 mannite, whereas the other three minerals analyzed are muth- 

 mannite with gold replacing part of the silver : they can be more 

 accurately described as auric muthmannite. 



ECONOMICS. — An objective standard of value — Correction and 

 addendum.— AijFbbd J. Lotka. Communicated by G. K. 

 Burgess. 



In the paper on this subject published in the issue of this 

 Journal dated August 19, 1914, the following changes should 

 be made: 



Page 413, in the first line of the paragraph following equa- 

 tion (6), for ''The ophelimities ^1,^2..." read: "The mar- 

 ginal ophelimities coi, 0^2 . . ." 



In the fourth Une of the same paragraph, for " the ophelimi- 

 ties" read: "the marginal opheHmities." 



Page 416, equation (13), for v"2 read v'2. 



Page 417, in the proportion (18), for v'l v'2 read v'i:v'2. 



Page 417. The method by which • the proportion (18) is 

 derived from equations (11) and (14) is inadequate. 



This proportion (18) follows by an application of the theory 

 of exchange, coupled with the principle introduced in this paper, 

 namely, that in a community in which the sense of value were 



