^04 -£• G. Spaulding 



Now just as it has been found previously that 



E = W+{U,-U,) [2] 



and that 



W+(U,-U,)=I'^J^ [8] 



and (p. 295), when it is known that we are deaHng with initial and 

 final pressures, with volume constant in an isothermal event, that 



E = V (pi- p.) 

 and that, therefore, 



fV+[U,-U,)^v {p,-p,) 



so here it is impossible to determine separately the two quantities, 

 fV and U2-U1; rather, the computation in accordance with the 

 values found for v, p^ and po_ gives only a resultant, namely, the 

 excess of the maximum w^ork done by the system over the simul- 

 taneous increase in its internal energy. This computation, fur- 

 thermore, has already been shown (p. 295) to be in accordance with 

 and a special case of our general formula [8], and, therefore, of the 

 Laws which it expresses. 



This relation can be further demonstrated as follows: 

 In equation [8] substitute for / the intensity factor p, and for 

 W the product p v, found in [i i]. Then, with t/, - f/i = o, as in the 

 case of the expansion of a perfect gas, we get 



The equation comes to identity, as is necessary. Nor would this 

 demonstration be altered in the case in which (Uo — U^ >o; for 

 (^2 - ^1) =E == W in accordance with the First Law, and so 

 might be set in equivalence with pv, and this substituted, with the 

 result an identical equation as before. 



By the results of the computation in accordance with the results 

 obtained from measurement, namely, that an original increase of 

 pressure following fertilization and a decrease of this following 

 each cleavage take place, while the temperature and volume 

 remain constant, the quantitative value of the resultant energy- 

 changes will, then, have been determined. But, in accordance 



