Radiation  from  Ordinary  Materials.  215 
case  of  poor  agreement.     Table  I.  gives  the  calculated  values 
of  —   for  different  values  of  a  and  ,r*. 
P 
Fio-.  16. 
Fiff.  17. 
1-0 
0-3 
03 
0-7 
0-6 
0-5 
C-4 
03 
0-2 
01 
4 
^ 
4 
0> 
c 
f 
/// 
7 
Tin 
ol^q 
i 
I 
ill 
i 
i 
0         I 
X 
*  For  the  calculation  of  this  table  I  am  indebted  to  the  industry  of 
my  brother,  Mr.  E.  R.  Campbell.     It  should  be  noted  that  —    is  very 
near  1,  when  x  approaches  «;  hence  the  curve  (A)  will  appear  straight 
before  the  ordinate  at  ,v=a  is  reached. 
