204 _ W. Gibbs on the wave lengths 
TABLE V (continued). 
K H ~ Ka (HA A E 
1°3 2186 487-19 487-29 -0°10 Co 
2103'3 2236, 484-665 484-48 +0718 Co 
2132°3 2286 48200 481-80 +0°20 Co 
21485 480°56 480-27 +029 Cd 
Q157°4 479°76 479-70 +0:06 Co 
2626°5 3156 444-61 444-45 +016 Pt 
828 441:90 441 7 +015 Ca 
438-75 438:5 Fe 
28223 3532 2-82 432-75 07 Fe 
1 431-77 431-92 -0-15 Ca 
2854-7 3507 * 431-03 430-92 +011 Fe 
2864°7 3617 430-79 430°36 +043 Ca 
2869-7 28 430-21 430°05 +0°36 G 
a 
_ In this table K represents the scale number upon Kirchhoft’s 
e 
much farther than this point. This is therefore probably the 
least reliable portion of my work, though as yet I have seen 
no reason to doubt its accuracy. For the portion of the scale 
between. A and C we possess very few measurements of wave 
possible, I have brought together in tables VI and VII all 
the measurements of wave lengths which I have been able t0 
a Ss rer Bae i 
Van der Willigen; column fifth, Ditscheiner’s measurements, 
reduced for the value of D,, given by Angstrém; column sixt®, 
Ditscheiner’s measurements, as given in his second paper,§ 12 
which the absolute value of the interval between two successiv? 
* Archives du Museé Teyler, vol. i, p. 1. Pogg. Ann., exxiii, p- 439. 
{ Sitzungsberichte der k. k. Akad. ee Wiastensebilters i, 1, 1864, 
§ Band lii, 289. : : ‘ 
Nore.—I have not been able to find in lie library in thi a Copy 
of the Annales Scientifiques de Tatts notasia ~ ite ap nad esr iy, cour 
taining an extended memoir on wave lengths by Mascart. 
a5 U 
é 
