bulae.
Apropos of the sun, Father Secchi, of the observatory at Rome, has
been questioning the great luminary with philosophical apparatus, to
ascertain whether any difference could be detected in the heat from
different parts of its surface, and the proportion lost in its passage
through the atmosphere. He finds that the equatorial region is the
hottest; and that, as on our earth, the temperature diminishes towards
the poles: it is in the central region that spots most frequently
appear. The result of the investigations is that, after allowing for
absorption, the heat which comes to the earth corresponds in amount to
that inferred from photometric experiments, whereby the experiments
made at Paris and at Rome confirm each other.

Now that Mr Fox Talbot has so praiseworthily given up his patent right
to Talbotypes, except in the matter of portraits, the art of
photography will find itself stimulated to yet further developments;
and with free practice, many new applications of it will be
discovered. Magic-lantern slides, for instance, obtained from the
negative image, are already lowered in price, while their style and
finish are singularly beautiful. The architect of the bridge now being
built over the Neva, at St Petersburg, is turning it to account in a
very practical manner. Being an Englishman, he has had to endure much
jealousy and misrepresentation, and attempts have been made to
prejudice the authorities against him. To counteract these designs, he
takes every week photographs of the work, which distinctly shew its
progress, and these he sends to the emperor, who looks at them in a
stereoscope of the largest size, and can thus satisfy himself of the
actual condition of the bridge by means which malice or envy would not
easily falsify. If the photograph shews finished arches, of what use
will it be to deny their existence? People out of Russia may perhaps
find it worth while to try the same experiment; and before long, a new
order of 'detectives' on elevated stations, will be taking photographs
of all that passes in the streets, and pickpockets _in delicto_ will
find their offence and their likeness imprinted by one and the same
process. With such a means of detection, and all the police stations
connected by telegraphic wires, what are the thieves to do?

Manchester shews itself earnest in the cause of education, by having
established a Free Library of 16,000 volumes for reference, and 5000
for lending, and pai