ARCH 6, 1903.] 



SCIENCE. 



391 



gas in both vessels, the same temperature ob- 

 taining throughout its entire mass. For how 

 could a differei^oe of temperature resiilt when 

 no other action between the molecules is pos- 

 sible than their collisions with one another, 

 collisions which cannot affect the molecule's 

 kinetic energy (the kinetic energy of each 

 molecule being the same according to our sup- 

 position). But if it is admitted that in the 

 supposed case the two vessels will be filled uni- 

 formly with the gas at the same temperature 

 throughout, it is also admitted that a portion 

 of the gas was set in motion of translation 

 without any work having been done. 



The only objection that could be raised to 

 the above reasoning is perhaps this : the gas, 

 while compressed in the receiver, has motion 

 of agitation and, after equilibrium is estab- 

 lished upon a portion of the gas having en- 

 tered the vacuous vessel, it has again the 

 same motion of agitation, but while passing 

 from the receiver into and through the vacu- 

 ous vessel a portion of the gas had, in addi- 

 tion, motion of translation which must be 

 superimposed on the motion of agitation. 

 There thus seems to be here a plus of energy 

 to be accounted for. But this objection can 

 be met by considering more closely the three 

 stages in time which the phenomenon of the 

 exijansion of a gas into a vacuum presents. 

 First, in the compression chamber all the gas 

 has only motion of agitation, then while tra- 

 versing the vacuous vessel the respective por- 

 tion of the gas has only or mainly motion of 

 translation at the expense of its original mo- 

 tion of agitation ; and lastly, on striking the 

 walls of the empty vessel the incoming gas 

 has its motion of translation reconverted into 

 motion of agitation. 



If the above reasoning is correct, it means 

 that just as to set one gas molecule in motion 

 of translation in a vacuum does not require 

 anything else than its own motion of agita- 

 tion (which will, I believe, be admitted by 

 every one), so with a body of gas. 



But if in the hypothetical case no change 

 in the magnitude of the kinetic energy of 

 the individual molecules is required to ' trans- 

 late ' (if I may use the expression) a portion 

 of the molecules, why should it be necessary 



in the actual case as understood on the basis 

 of the kinetic theoi-y? It is true that we 

 observe here a redistribution of energy and 

 a ' translation ' of a portion of the gas, but 

 this ' translation ' would have taken place if 

 there were no redistribution of energy. 



Peter Fireman. 

 Washington, D. C. 



will-making. 



To THE Editor of Science : The ever-recur- 

 ring contests of wills, the disputes as to their 

 validity, their meaning in general and par- 

 ticular, the interpretation of their peculiar- 

 ities and seeming inconsistencies, etc., are 

 such a damage to private comfort and to the 

 public welfare in the highest sense, that any 

 means of lessening the growing evil must be 

 welcomed by all concerned. 



As part remedy at least, I would suggest the 

 establishment by each state of a court or other 

 properly constituted body, whose duty and 

 business it should be, upon application, to 

 consider and validate during the lifetime of 

 the testator his will, which, after approval 

 could be deposited with the necessary secrecy, 

 as a thoroughly competent legal instrument. 

 To change a will, the same process should be 

 gone through again. This presentation, vali- 

 dation and placing on record should absolutely 

 bar all actions designed to break or alter the 

 will after the death or subsequent incapacity 

 of the testator. The way in which the Tor- 

 rens land-title has been instituted in some 

 countries is, if not a precedent, an instance 

 of the successful treatment of a kindred diffi- 

 culty. An unbreakable will might turn out to 

 be as great a boon as an indefeasible title. 

 Alexander F. Chamberlain. 



Claek University, Worcester, Mass., 



[It is said of Charles Darwin in the ' Life 

 and Letters ' : ' He would declare energetically 

 that if he were law-giver no will should be 

 valid that was not pviblished in the testator's 

 lifetime.' It is not clear how a secret will 

 could be validated in the manner suggested 

 by Professor Chamberlain, but there appears 

 to be no reason why it should not be possible 

 to probate a will during the lifetime of the 

 testator. Such legal and moral scandals as 



