+-------------------+--------+------+-------------------------+ | Date. | Wind. |Ozone.| Aurora. | +-------------------+--------+------+-------------------------+ |1871, April 8th| S.S.E. | 5 |Aurora on 9th, but | | ” ” 9th| S.S.E. | 8 | wind E. and unfavourable| | ” ” 10th| S.E. | 5 | to ozone. | +-------------------+--------+------+-------------------------+ |1871, November 9th| N. | 5 |Aurora on all three | | ” ” 10th| N.W. | 8 | nights. | | ” ” 11th| N. | 5 | | +-------------------+--------+------+-------------------------+ |1872, February 3rd| S.W. | 4 |Aurora on night of the | | ” ” 4th| S.S.W. | 5 | 4th represented by | | ” ” 5th| S.W. | 8 | ozone-paper of morning | | ” ” 6th| S.W. | 5 | of the 5th. | +-------------------+--------+------+-------------------------+ Other cases are, we are bound to say, found, in which ozone was either not remarkable for quantity, or positively fell during the Aurora, as, for instance, this:— +-----------------+------+------+------------------------------+ | Date. | Wind.|Ozone.| Aurora. | +-----------------+------+------+------------------------------+ |1874, March 16th |W.N.W.| 6 |Aurora on the 18th represented| | ” ” 17th | S.W. | 6 | by test-paper of | | ” ” 18th | W. | 5 | the 19th with only two | | ” ” 19th |S.S.W.| 2 | degrees of discoloration. | +-----------------+------+------+------------------------------+ It is, however, possible that such instances may be accounted for, either by some reaction on the test-papers after they have been coloured, or by some accidental antagonistic circumstance affecting the tests. The following is a case well illustrating this:— +------------------+------+------+---------------------------------+ | Date. | Wind.|Ozone.| Aurora. | +------------------+------+------+---------------------------------+ |1874, January 31st|N.N.W.| 6 |There was an Aurora on | | ” February 1st| N.W. | 8 | the night of the 2nd represented| | ” ” 2nd| N.W. | 2 | by the ozone-paper | | ” ” 3rd|N.N.W.| 4 | (4 only) on the | | ” ” 4th|E.N.E.| 8 | morning of the 3rd. | +------------------+------+------+---------------------------------+