| Date. | Aurora. | Ozone. | |||
|---|---|---|---|---|---|
| 1870, | October | 14th. | Aurora. | 8 | The display of the 24th was accompanied by the formation of a corona, and that of the 25th was splendidly seen in Edinburgh. |
| ” | ” | 20th. | Aurora. | 10 | |
| ” | ” | 21st. | None seen. | 5 | |
| ” | ” | 22nd. | Aurora. | 10 | |
| ” | ” | 23rd. | None seen. | 8 | |
| ” | ” | 24th. | Aurora. | 10 | |
| ” | ” | 25th. | Aurora. | 8 | |
The foregoing figures somewhat point to the conclusion that ozone quantity rises and falls coincidently with the Aurora displays.
The following seems, however, a case still more strongly in point.
| Date. | Wind. | Aurora. | Ozone. | ||
|---|---|---|---|---|---|
| 1871, | January | 25th. | E.S.E. | None seen. | 0 |
| ” | ” | 26th. | N.N.W. | None seen. | 2 |
| ” | ” | 27th. | E.S.E. | Aurora at night in N. and S. horizons. | 10 |
| ” | ” | 28th. | E. | None seen. | 8 |
| ” | ” | 29th. | S.E. | None seen. | 2 |
It is curious, in examining the above Table, to note how the ozone rose, notwithstanding an east wind, from 0 on the 25th, and 2 on the 26th, to 10 on the 27th, when the Aurora appeared, and 8 on the 28th, when it might have lingered; and how it again descended to 2 on the 29th.
The case of the Aurora of 6th of October, 1869, when a broad belt of Aurora was in the north, is also an illustrative one, as will be seen by the following data:—
| Date. | Wind. | Ozone. | Aurora. | ||
|---|---|---|---|---|---|
| 1869, | October | 5th. | S.S.W. | 1 | — |
| ” | ” | 6th. | S.S.E. | 5 | Aurora. |
| ” | ” | 7th. | S.S.W. | 10 | — |
| ” | ” | 8th. | S. | 10 | — |
| ” | ” | 9th. | S.E. | 5 | — |
The Aurora of the night of the 6th was here represented by the ozone-paper of the morning of the 7th with a maximum of 10, which lasted till the 8th.
[It should be borne in mind, in examining these Tables, that the Aurora is of the night of the given date, while the ozone-papers are taken and recorded in the morning of the date quoted.]