18 



KXPEniMENTS WITH I<»NIZKI> AlK. 



j)t'r iiiiiiute iiece.ssary to protluce the full blue of the first onU'f is put equal to one 

 unit. The volume ratio for all the other colors is then the equivalent, in the .same 

 scale, of the numbers of particles necessary to produce them, provided that the air 

 passing through the phos[ihoius ionizer is discharged in the same state of saturation, 

 and there is uo other variation of the steam jet and color tube during the experiment. 

 The table also gives the volume in litres per minute in case of each standard blue 

 taken. As this datum is on the average of the order of .5 liters/ niiu., the 

 tabulated volumes F aie in a general way about twice the absolute mean volumes. 

 The use of the standard blue for reference is unavoidable, so long as the precise 

 conditions under which phosphorus emanates are not understood. 



The recipiocal of the volume ratio V will vary as the bulk of the steam 

 globiile produced, supposing that the supersaturation which i)iecedes condensation 

 has remained constant. Thus there must be no change in the pressure of the 

 steam jet oi- in the tempei-ature of its environment. The cube root of the reciprocal 

 of the volume ratio might then be called the diametei- of the particle. It will be 

 shown below, however, that variations of d and 2> iii"« not of the importance 

 which one would attach to them at the outset. 



The table consists of 4 parts of which the first is preliminary, the second at a 

 relatively high room temperature, promoting the occurrence of the browns of the 

 first order but giving very faint tints of the second order. The thii'd part at 

 relatively low room temperature (e) favois the second order of colors but termi- 

 nates in opaque of the first order. In the fourth part the air was taken from the 

 outside of the room and warmed in the steam drum. The last part is incidental. 



Table I. 



Each part of this table contains successive series of data obtained on ditt'eieut 

 days, as a rule. In all there are 23 series. 



TABLE 1, PART I, PRELIMINARY.— COLOR AND RELATIVE NUMBER OF PAR- 

 TICLES. BLUE = " I." RELA TIVE BULK AND DIAMETER. 



