Oe Re Pe ax: ADDENDUM vo Part V. 
Nore:—Since publishing this paper, Mr. gone has called my attention to a point i in which [ incon- 
-siderately misunderstood his paper in my allusion to it, onthe first paragraph of page 63. What he has shown 
in the paper referred to is not that the distribution of velocities represented by two streams of unpolarised 
gas is the ultimate state towards which the gas tends when the number of molecules is indefinitely 
diminished, but that as long as there are considerable numbers of molecules present the actual state of the 
gas lies between that represented by mutually non-interfering streams and an unpolarised state. Asthe 
number of molecules diminishes indefinitely the tendency is towards a state which might be represented 
by the radii drawn from a common centre to two hemispheres of unequal radius turned in opposite direc- _ 
tions, the one of larger radius being turned from the heater. In this case it is easy to see that there would 
be no difference between the pressures in the direction of the transference of heat and in the perpendicular 
direction, and consequently no Crookes’s force. 
\ 
’ bite: Corrtannna TO PART Ye 
| 4 Page 57, line 12 from top, for presure read pressure. 
or . Re eOlsaies., 6) bottom, ,, k = K. 
a 7 wo 0% gy Of top, ” K ” . ” 
» GB » Ll » botiom , © » &, 
» 8 » YD » OD, 9 | bs 0 Key 
