t as to its origin. In the latter
part of 1902 an extraordinary diminution was found in the intensity of
the sun's heat, as measured by the bolometer and other instruments.
This continued through the first part of 1903, with wide variations at
different places, and it was more than a year after the first
diminution before the sun's rays again assumed their ordinary intensity.

This result is now attributed to the eruption of Mount Pelee, during
which an enormous mass of volcanic dust and vapor was projected into
the higher regions of the air, and gradually carried over the entire
earth by winds and currents. Many of our readers may remember that
something yet more striking occurred after the great cataclasm at
Krakatoa in 1883, when, for more than a year, red sunsets and red
twilights of a depth of shade never before observed were seen in every
part of the world.

What we call universology--the knowledge of the structure and extent of
the universe--must begin with a study of the starry heavens as we see
them. There are perhaps one hundred million stars in the sky within the
reach of telescopic vision. This number is too great to allow of all
the stars being studied individually; yet, to form the basis for any
conclusion, we must know the positions and arrangement of as many of
them as we can determine.

To do this the first want is a catalogue giving very precise positions
of as many of the brighter stars as possible. The principal national
observatories, as well as some others, are engaged in supplying this
want. Up to the present time about 200,000 stars visible in our
latitudes have been catalogued on this precise plan, and the work is
still going on. In that part of the sky which we never see, because it
is only visible from the southern hemisphere, the corresponding work is
far from being as extensive. Sir David Gill, astronomer at the Cape of
Good Hope, and also the directors of other southern observatories, are
engaged in pushing it forward as rapidly as the limited facilities at
their disposal will allow.

Next in order comes the work of simply listing as many stars as
possible. Here the most exact positions are not required. It is only
necessary to lay down the position of each star with sufficient
exactness to distinguish it from all its neighbors. About 400,000 stars
were during the last half-century listed in this way at the observatory
of Bonn by Argelander, Schonfeld, and their assistants. This work is