en, uranium.
_Not in Solar Spectrum._--Antimony, arsenic, bismuth, boron, nitrogen
(vacuum tube), caesium, gold, iridium, mercury, phosphorus, rubidium,
selenium, sulphur, thallium, praseodymium.
Oxygen was added to the solar ingredients by Runge and Paschen in 1896,
gallium by Hartley and Ramage in 1899. Lithium may be admitted
provisionally, and the chromospheric constituent helium takes rank,
since 1895, as a chemical element.
TABLE III.
EPOCHS OF SUN-SPOT MAXIMUM AND MINIMUM FROM 1610 TO 1901.
+----------+----------++----------+----------+----------+----------+
| Minima. | Maxima. || Minima. | Maxima. | Minima. | Maxima. |
+----------+----------++----------+----------+----------+----------+
| 1610.8 | 1615.5 || 1712.0 | 1718.2 | 1810.6 | 1816.4 |
| 1619.0 | 1626.0 || 1723.5 | 1727.5 | 1823.3 | 1829.9 |
| 1634.0 | 1639.5 || 1734.0 | 1738.7 | 1833.9 | 1837.2 |
| 1645.0 | 1649.0 || 1745.0 | 1750.3 | 1843.5 | 1848.1 |
| 1655.0 | 1660.0 || 1755.2 | 1761.5 | 1856.0 | 1860.1 |
| 1666.0 | 1675.0 || 1766.5 | 1769.7 | 1867.2 | 1870.6 |
| 1679.5 | 1685.0 || 1775.5 | 1778.4 | 1878.9 | 1884.0 |
| 1689.5 | 1693.0 || 1784.7 | 1788.1 | 1890.2 | 1894.0 |
| 1698.9 | 1705.5 || 1798.3 | 1804.2 | 1901.9 | |
+----------+----------++----------+----------+----------+----------+
TABLE IV.
MOVEMENTS OF SUN AND STARS.
1. Translation of Solar System.
+----------------------------+-------------------------+-------+
| Apex of Movement. | Authority. | Date. |
+----------------------------+-------------------------+-------+
| R. A. Dec. | | |
| | | |
| 277 deg. 30' + 35 deg. | Newcomb | 1898 |
| 273 deg. 36' + 29 deg. 30' | Kapteyn | 1901 |
| 279 deg. + 46 deg. | Porter | 1901 |
| 275 deg. + 45 deg. | Boss | 1901 |
| 277 deg. 30' + 20 deg. | Campbell (from stellar | 1902 |
| | spectroscopic measures) | |
+----------------------------+-------------------------+-------+
| Velocity = 12.4 miles p
|