2. Luminous Appearances in the Atmosphere.
3. On the Determination of the Mean Temperature of the Air.
v = 12 (x f + xe)−0.33 + 0.41 sin. [(n−1) 30° + 124° 8′] v = mean temperature. n = the ordinal number of the month for which the temperature is to be calculated (thus, for March, n = 3). 12 (x f + x e) = the mean temperature taken as the mean of observations taken at ten o’clock in the morning and evening. In winter 12 (x f + x e) = v very nearly; whilst, in summer, this quantity is 34 of a degree greater than v at Paris, Halle, and Abo.—Annal. der Phys. und Chem. 1825, p. 373.
4. Indelible Writing.
5. Peculiar Crystals of Quartz.
6. Native Iron not Meteoric.
The specimen has been examined chemically, by Mr. Shepherd, at Yale College. It is invested with highly crystalline plumbago, and splits by the intervention of plates of plumbago into pyramidal and tetrahedral masses. It is not equal to meteoric iron in malleability, toughness, and flexibility, and has not the silvery white appearance of that iron. Its specific gravity is from 5.95 to 6.72. It has native steel intermingled in it, but contains no nickel, or any other alloy.
Major Barrall has only been to the place where this iron occurred once, and no other person has ever been to the place, or knows where it is.—Silliman’s Journal, xii. 154. [p225]
7. Native Argentiferous Gold.
| Native Gold of Marmato.—Pale yellow octoedral crystals: | |||
| Gold | 73.45 | 3 atoms | 73.40 |
| Silver | 26.48 | 1 " | 26.60 |
| Loss | 00.07 | ||
| Native Gold of Titiribi: | |||
| Gold | 74.00 | 3 atoms | 73.40 |
| Silver | 26.00 | 1 " | 26.60 |
| Native Gold of Malpaso.—Yellow irregular flattened grains: | |||
| Gold | 88.24 | 8 atoms | 88.04 |
| Silver | 11.76 | 1 " | 11.96 |
| Native Gold of Rio-Sucio.—Deep-coloured large irregular grains: | |||
| Gold | 87.94 | 8 atoms | 88.04 |
| Silver | 12.06 | 1 " | 11.96 |
| Native Gold of the Otra Mina.—Pale yellow octoedral crystals: | |||
| Gold | 73.4 | 3 atoms | 73.40 |
| Silver | 26.6 | 1 " | 26.60 |
| Native Gold of Guamo.—Brass-yellow indeterminate crystals: | |||
| Gold | 73.68 | 3 atoms | 73.40 |
| Silver | 26.32 | 1 " | 26.60 |
| Native Gold of Llano.—Small flattened grains—reddish: | |||
| Gold | 88.58 | 8 atoms | 88.04 |
| Silver | 11.42 | 1 " | 11.96 |
| Native Gold of Baja.—Porous: | |||
| Gold | 88.15 | 8 atoms | 88.04 |
| Silver | 11.85 | 1 " | 11.96 |
| Native Gold of Ojas-Anchas.—Yellowish red plates: | |||
| Gold | 84.5 | 6 atoms | 84.71 |
| Silver | 15.5 | 1 " | 15.29 |
| Native Gold of Trinidad, near Santa Rosa de Osos.—A solid piece of 50 grains: | |||
| Gold | 82.4 | 4 atoms | 82.14 |
| Silver | 17.6 | 1 " | 17.86 |
| Native Gold of Transylvania (Europe).—Pale yellow cubic crystals: | |||
| Gold | 64.52 | 2 atoms | 64.77 |
| Silver | 35.48 | 1 " | 35.23 |
| Native Gold of Santa Rosa de Osos.—A mass weighing 710 grains: | |||
| Gold | 64.93 | 2 atoms | 64.77 |
| Silver | 35.07 | 1 " | 35.23 |