_the magnitude of the diurnal motion_. From the hourly observations,
conducted in this observatory since the month of August, 1840, we
ascertain the following to be the magnitude of the diurnal motion for
each month separately."

+-------------------------------------------------------------------+
| | Jan. | Feb. | March.| April.| May. | June. | July. | Aug. |
+-------------------------------------------------------------------|
| 1841 | 3.72 | 5.13 | 8.43 | 11.49 | 11.47 | 11.49 | 10.07 | 9.86|
| 1842 | 3.65 | 4.74 | 8.34 | 10.33 | 9.31 | 9.78 | 8.38 | 9.03|
| 1843 | 3.82 | 4.08 | 6.87 | 9.71 | 9.24 | 10.14 | 9.57 | 10.08|
| 1844 | 2.81 | 3.43 | 6.95 | 9.53 | 8.42 | 8.88 | 8.38 | 9.28|
| 1845 | 2.20 | 4.69 | 8.26 | 11.93 | 10.88 | 10.73 | 9.44 | 10.42|
| 1846 | 3.30 | 6.94 | 9.53 | 12.27 | 12.58 | 11.21 | 11.37 | 11.49|
| 1847 | 3.30 | 6.35 | 9.85 | 12.43 | 11.81 | 11.76 | 10.94 | 12.87|
| 1848 | 6.52 | 9.01 | 11.96 | 14.56 | 14.22 | 13.80 | 14.67 | 15.40|
| 1849 | 7.27 | 8.42 | 14.08 | 16.86 | 13.67 | 13.86 | 12.57 | 11.54|
| 1850 | 5.98 | 8.84 | 12.15 | 14.32 | 14.05 | 13.39 | 12.53 | 12.68|
+-------------------------------------------------------------------+
+----------------------------------------------------+
| Sept. | Oct. | Nov. | Dec. | Autmn | Spring| Year.|
| | | | |& Wint.| & Sum.| |
|----------------------------------------------------|
| 8.78 | 6.82 | 3.71 | 2.89 | 5.12 | 10.53 | 7.82|
| 7.72 | 7.05 | 3.86 | 2.81 | 5.07 | 9.09 | 7.03|
| 8.81 | 6.82 | 3.82 | 2.79 | 4.70 | 9.59 | 7.15|
| 8.23 | 6.54 | 3.94 | 2.98 | 4.44 | 8.79 | 6.61|
| 8.82 | 7.34 | 4.49 | 8.34 | 5.89 | 10.87 | 8.13|
| 10.39 | 7.82 | 5.66 | 3.22 | 6.08 | 11.25 | 8.81|
| 12.06 | 11.53 | 7.06 | 4.70 | 7.63 | 11.98 | 9.55|
| 14.00 | 10.30 | 5.78 | 3.53 | 7.85 | 14.44 | 11.05|
| 10.79 | 9.12 | 5.41 | 4.09 | 8.06 | 13.21 | 10.64|
| 12.64 | 9.04 | 6.20 | 3.45 | 7.61 | 13.27 | 10.44|
+----------------------------------------------------+

The Philadelphia and Toronto observations disclose the same state of
facts.

Dr. Lamont, also, in his article, gives us the following table of the
magnitude of the variations derived from observations at Gottingen:

+--------------------+