Chemistry and Physics. 297 
s rivers ; thence east to the place 
of beginning; is hereby reserved and withdrawn from settlement, 
occupancy, or sale under the laws of the United States, and dedi- 
py the same, or any part thereof, 
cept as hereinafter provided, shall be considered trespassers and 
said park, and against their capture or destruction for the pur- 
Ses of merchandise or profit Il also cause all 0 
trespassing upon the same after the passa f oO 
such measures as shall be necessary or proper to fully carry out 
the objects and purposes of this act. 
Approved, March 1, 1872. 
SCIENTIFIC INTELLIGENCE. 
IL CHEMISTRY AND PHYSICS. 
1. On the wave-lengths of Fraunhofer’s lines.—DrtscuEiNeR has 
recomputed the values of the wave-lengths determined by himself 
after again counting the lines upon his ruled plate of glass. The 
total breadth of the ruled surface was found to be 13°8765 milli- 
Meters and the number of lines 3001. Ditscheiner’s values, with 
the corresponding ones as determined by Angstrom and van der 
