accounting
for the rapid changes of those spots. The escape of such a vast quantity
of gas from the interior of the body of the sun would, he observes, as it
surrounds that luminary, produce that bright and dazzling appearance which
is the atmosphere of the sun. This theory may not accord with the opinions
of others who have made observations on the subject; but the writer, at
any rate, entertains the strongest belief of its truth. With the same
instrument, which is but just finished, he has also examined the moon, and
states his conviction that that body is covered with perpetual snow and
ice, the dark spots discoverable on its surface being frozen seas, and the
lighter spaces land covered with snow. Those circular places, which have a
rising cone in the centre, he thinks are extinguished volcanoes, as no
clouds are perceptible over the moon's face; which being covered with snow
and ice, accounts, as he imagines, for its clear atmosphere, or for the
absence of an atmosphere. This vast accumulation of ice and snow upon the
moon's surface may be explained, the writer conjectures, by the nature of
the moon's revolutions. He offers to construct instruments of the above
description, by which these phenomena may be observed, at prices from 50
to 100 dollars; and at the same rate to furnish solar microscopes, on a
new principle, with a magnifying power at 12 feet distance, of
5,184,000.--_Boston Bulletin_.

_National Repository_.

Nearly two hundred specimens of curious works in arts and manufacture have
already been laid before the committee of this establishment; the opening
of which will take place in a few days.

_Iron Trade_.

In 1820, the whole iron made in Great Britain was 400,000 tons: in 1827,
it had increased to 690,000 tons, from 284 furnaces. About three-tenths of
this quantity are of a quality suitable for the foundry, which is all used
in Great Britain and Ireland, with the exception of a small quantity
exported to France and America. The other seven-tenths are made into bars,
rods, sheets, &c., of which a large quantity is exported to all parts of
the world.--_Repertory of Arts_.

_Indian Claystone_.

In some parts of India, the claystone contains numerous small _nodules_ or
lumps of clay iron-stone, which seldom exceed the size of a walnut. These
are picked up by the natives, and are smelted by means of charcoal in a
very small, rude furnace, blown by the hand-bellows, common all over
India