294 F. V. Hayden— Yellowstone National Park. 
the experimental valuation adopted by Tyndall (1-421), and is 
virtually identical with the mean result of the experiments of 
Dulong, and Favre and Silbermann, upon ether and olive oil 
(1-494 and 1495), as well as with the theoretical volumetric con- 
densation of H,O (1°5). 
If my postulates are admitted, the field which they open for 
the verification of astronomical, thermal, electrical and chemi- 
cal observations and experiments, seems unlimited. have 
already in view special researches pertaining to solar tempera- 
ture, zthereal density, atomicity and valency, specific and 
latent heats, temperature of fusion, vaporization and dissocia- 
tion, mixtures of gases and vapors, periods of planetary rota- 
tion, terrestrial rigidity and tides. 
. Philadelphia, Feb. 20, 1872. 
Art. XLL—The Yellowstone National Park ; by ¥. V. HAYDEN. — 
ith a Map. 
the Senate of the United States, by the Honorable S. C. i 
€roy, to set apart a certain tract of land lying near the hea 
waters of the 
