784 
T Ave are al 
min A, Roemer | Bene S| am a, ge 
4358 93.85 18.6 35.74 1.00 
4047 93.9 18.3 30.18 1.18 
3665 GOD del 25.65 1.455 
3130 68.17) 47.0) 17-30 2.145 
3190 276.0 3)” AND 20.45 — 
2805 75.2 19.8 15.69 2.83 
2654 15.5 19.7 13.44 3.29 
2535 74.9 20.9 12.19 3.67 
2482 | 75.0 20.5. 11.44 3.905 
2300 | 14.1 19.3 10.44 4.27 
2378 74.8 10.3 10.19 4.37 
By calculating values of &)/R,,,, from these measurements we 
can compare the results obtained with the Leiden and with the 
Oxygenium hydrogen : 
Apes MENEN, 
: Ri lRaos: R. ie 
A 4 A 
taal Leiden Oxygenium 
4047 1.00 1.00 
3665 I 2483 1.235 
3130 1.815 1.79 
2805 | 2.39 2.40 
2654 2.78 2.755 
2535 3.109 3.14 
2482 3.30 3.355 
As the photographs for the last ultraviolet lines were much sharper 
for the Leiden hydrogen, | have used the values obtained with it 
« o 
for the construction of the dispersion curves. 
| 
Carbon-dioxide. 
8. For this the rotatory constants are greater than for the other gases. 
e o 
The measurements were made at a pressure of 27 atm. as at higher 
pressures small temperaturefluctuations gave rise to currents in the 
gas, which rendered the image of the slit indistinct. 
