As the planet now went away and detail should have dimmed, the Brontes proceeded to do the opposite. One had almost said it was actuated by a spirit of contrariety. For now when it had reason to grow faint it grew in conspicuousness; just as, before, when it should have become evident, it had declined. Distinctly farther off and smaller as the planet was at the next presentation, the Brontes had clearly developed both in tone and in the amount of it visible. This was in May (Drawings IV and V). In June bad seeing prevented good observations, but in July, Drawing VI, when the region again came round, the Brontes, in spite of the then greatly increased distance, asserted itself so strongly that even in not very good seeing its presence could not be passed by.
V. May 7.
This contrariety of behavior had about it one very telling feature. That the canal waxed or waned in exact opposition to distance and even toward the last to seeing too, showed conclusively that neither distance nor definition could in any way be held responsible for its metamorphoses. A very fortunate circumstance, this of the observations, for it directly eliminated size of disk, phase, and seeing, for which correction are none too easy to make, and which in the minds of the sceptical could always remain as unexplained possibilities of error.
VI. July 18.
The mean-canal cartouches show synthetically, and all the more conclusively for being composite, the laws of the flux of the canals. Something more of vividness, however, is imparted by the actual look of one of the constituents during the process. It is the difference between seeing a composite picture made from a given group of men and the gazing on the actual features of any one of them. So much is gained by the drawings across the page of the Brontes at different stages of its evolution during the period here concerned. But in another way, too, the one canal may be made to yield a more lifelike representation of the process than a number taken together are capable of affording. In the mean-canal cartouches each canal is treated as an entity; but it is possible to consider a canal by parts, and by so doing to see it in action, as it were. It occurred to me to treat the Brontes in this way. For this purpose I divided the canal into sections, five of them in all, between the point where it left the Propontis, at a spot called the Propropontis, to where it ended in the Sinus Titanum. The first, the most northern, extended as far as Semnon Lucus, the southernmost outpost of the Propontis congeries of spots. The second continued on from these to Eleon, the junction where the Erebus crossed. The third thence to Utopia, where the canal met the Orcus; the fourth to an arbitrary point in latitude 8° south, and the fifth and last to the Sinus Titanum. The lengths of these sections were respectively: 12°, 16°, 15°, 12°, and 13°. Each of the sections was then treated as if it were a separate canal and its cartouche found. To the cartouches’ determination there were available drawings:
| January 21-25 | 12 drawings. |
| February 23-March 2 | 15 drawings. |
| March 28-April 5 | 14 drawings. |
| April 26-May 8 | 27 drawings. |
| June 3-16 | 6 drawings. |
| July 11-21 | 16 drawings. |
| 90 drawings in all. |
The cartouches are given in the plate opposite, which is constructed precisely like the one for the mean canal cartouches presented on page [298]. The mid-latitude of the section and its mid-longitude are given in the margin with its description.
