which they are all
provided, sails can be hoisted, and the the double power of mules and
wind be put in requisition. This description of boat is getting to be
quite fashionable on the Illinois and tributaries, and some two or
three extend their trips to this city. They are a great benefit in low
water, as they are of exceeding light draught, and the running of them
is attended with but trifling expense. We learn that several new ones
are in a state of completion, on the line of the Illinois, intended as
regular traders up the Sangamon river, and from the head of navigation
on the Illinois to this city. There is nothing like enterprise, or a
mule boat on the Illinois, in a low stage of water, to get
along.--[St. Louis New Era.

=Discovery of Glass.=

'As some merchants,' says Pliny, 'were carrying nitre, they stopped
near a river which issues from Mount Carmel. As they could not readily
find stones to rest their kettles on, they used for this purpose some
of these pieces of nitre. The fire, which gradually dissolved the
nitre, and mixed it with the sand, occasioned a transparent matter to
flow, which in fact was nothing less than glass.'

=Pumping the water out of Lake Michigan.=

It is well known to our readers that, by an arrangement with the
English bond holders, the State of Illinois has given over to them the
unfinished canal, from the waters of Lake Michigan, at Chicago, to the
Illinois river.--They are about completing it, but the principal
difficulty now is, to supply it with water, owing to the level of the
lake being _eight_ feet below the bottom of the canal. To overcome
this, the present company, after various propositions, finally
bethought themselves of raising the water of the lake, so as to supply
the canal. They went to Messrs. Knapp & Totten, of this city, and
furnished them with a data to calculate whether it could be done, and
what force and what machinery would accomplish it. These gentlemen
soon furnished an answer to build some powerful machinery for that
purpose,--a steam engine and _eight_ pumps of four and a half bore and
six feet stroke. We are glad to hear that this eminently scientific
firm have been selected to execute this order. Their shop and
mechanical force are not excelled by any establishment in the United
States.--[Pittsburg Gaz.

=The Self-Regulating Ventilator.=

[Illustration:]

Explanation:--This is a cheap and simple but scientific apparatus for
regulating the air-