me others. While the list is a considerable one, I shall be
able to compress the statement of results for many of the series into
a short space.

[Sidenote: Provisional nature of results.]

"In connection with this synopsis of the scope of the investigations,
one or two particulars may be of interest, which at the present
writing seem to foreshadow the probable outcome. I beg, however, that
the statement will be regarded merely as a provisional one. First,
while the period is manifestly subject to change, as has already once
or twice been intimated, I have hitherto failed in tracing the
variations to any regular law, expressible in a numerical formula.
Indeed, the general impression produced by a study of these changes
in the length of the period is that the cause which produces them
operates capriciously to a certain degree, although the average
effect for a century has been to diminish the velocity of the
revolution of the pole. How far this impression is due to the
uncertainty of the observations, and to the complication of the
phenomenon with other periodical changes of a purely instrumental
kind, I cannot say. Almost all of the series of any extent which have
been examined, have the peculiarity that they manifest the
periodicity quite uniformly and distinctly for a number of years,
then for a while obscurely. In some cases, however, what at first
appears to be an objective irregularity proves not to be so by
comparison with overlapping series at other observatories.

"Another characteristic which has struck my attention, although
somewhat vaguely, is that the variations in the length of the period
seem to go hand in hand with simultaneous alterations in the
amplitude of the rotation; the shorter periods being apparently
associated with the larger coefficients for the latter. The
verification of these surmises awaits a closer comparative scrutiny,
the opportunity for which will come when the computations are in a
more forward state. If confirmed, these observations will afford a
valuable touchstone, in seeking for the cause of a phenomenon which
now seems to be at variance with the accepted laws of terrestrial
rotation."

[Sidenote: Reception of discovery.]

Let us now for a few moments turn aside from the actual research to see
how the announc