158 Earthquake Commotion and Sun Spots . [March, 
wane, from those hours until the present disastrous phase, 
when the issue of “ Whitaker’s Almanack ” is as black with 
earthquake phenomena as the sun has been dim with 
maculae. 
Why, then, we may now ask, Is the moon pitted over with 
huge volcanic mountains? And the answer is plain. Simply 
because more exposed it is baked and frozen in turn until its 
bronzed surface has become all cicatrised over from the 
alternate contraction and expansion of its soil, and its history 
has become as indelibly written in sun tremors as the 
story of this globe is told in billowy hills and up-turned 
strata. 
All this I learn from my seismic table. To-day I have 
accomplished a feat, and entered on a region imperfectly, if 
at all, known. I have constructed a table showing the years 
of maxima and minima sun spots between 1880 and 1500, 
with a good index to others, reaching back to the year o. 
As I look upon this little history of this great earth before 
telescopes and rain-gauges were, I seem to see the shadow 
on the paper of those great laws that rule the nebulae of 
suns, that hang out on dark space like mackerel clouds in 
the evening stillness. But the matter in detail is prosaic. 
During the period in which I have indicated the work of 
chronicling as the more feasible, I discover the differences 
intervening between the known sun phases in Wolff’s table 
will point the periods of commotion back to 1500, and that, 
although I get no recurring differences accurately speaking, 
here and there, there come on, in a remarkable manner, 
certain long periods when the lapse between the maximum 
and minimum of spots is 10, and this, likewise, at stated 
intervals. 1788 to 1798, 1657 to 1667, 1521 to 1531. These 
dates, as far as I can determine, fairly signalise the maxima 
and minima points of the progressive change in the east and 
west variation of the magnetic needle. Otherwise, there is 
a great uniformity presented in the cycles. Between 1855 
and 1755 the number of epochs of the maximum and mini- 
mum of spots works out as 18, between 1755 and 1655 the 
same, between 1655 and 1555 the same. This result, I should 
state, is given wholly by the breaks in the seismic tables, 
and I gain much confidence in my work from the circum- 
stance of this same uniformity. 
It will thus be seen that the dependence of the greater 
cycles of terrestrial magnetism, indicated by the east and 
west deviation of the compass needle, is indicated as being 
dependent on the shorter sun spot cycles. May it not, then, 
be likewise that the inclination of our globe to the sun, as 
