o find that it began twenty seconds before the
predicted time. The mathematical problems involved in correcting this
error are of such complexity that it is only now and then that a
mathematician turns up anywhere in the world who is both able and bold
enough to attack them.

There now seems little doubt that Jupiter is a miniature sun, only not
hot enough at its surface to shine by its own light The point in which
it most resembles the sun is that its equatorial regions rotate in less
time than do the regions near the poles. This shows that what we see is
not a solid body. But none of the careful observers have yet succeeded
in determining the law of this difference of rotation.

Twelve years ago a suspicion which had long been entertained that the
earth's axis of rotation varied a little from time to time was verified
by Chandler. The result of this is a slight change in the latitude of
all places on the earth's surface, which admits of being determined by
precise observations. The National Geodetic Association has established
four observatories on the same parallel of latitude--one at
Gaithersburg, Maryland, another on the Pacific coast, a third in Japan,
and a fourth in Italy--to study these variations by continuous
observations from night to night. This work is now going forward on a
well-devised plan.

A fact which will appeal to our readers on this side of the Atlantic is
the success of American astronomers. Sixty years ago it could not be
said that there was a well-known observatory on the American continent.
The cultivation of astronomy was confined to a professor here and
there, who seldom had anything better than a little telescope with
which he showed the heavenly bodies to his students. But during the
past thirty years all this has been changed. The total quantity of
published research is still less among us than on the continent of
Europe, but the number of men who have reached the highest success
among us may be judged by one fact. The Royal Astronomical Society of
England awards an annual medal to the English or foreign astronomer
deemed most worthy of it. The number of these medals awarded to
Americans within twenty-five years is about equal to the number awarded
to the astronomers of all other nations foreign to the English. That
this preponderance is not growing less is shown by the award of medals
to Americans in three consecutive years--1904, 1905, and 1906. The
recipients were Hale, Boss, and Ca