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BARNES' VENTILATOR FOR MATTRESSES, ETC.

Many diseases are caused by the use of beds not properly aired; and
it is difficult, if not impossible, to properly air, or ventilate,
a mattress, made in the usual manner. If this could be done more
thoroughly than it generally is, much sickness would be avoided.

[Illustration]

To secure this object cheaply and efficiently is the design of the
invention herewith illustrated. By it a complete circulation of
air through the mattress is secured, which carries off all dampness
arising from constant use. Thus the mattress becomes more healthy for
sleeping purposes, more durable and better fitted for the sick room.
The ventilators consist of coiled wire, covered with coarse cloth
(to prevent the stuffing closing up the tube), running through the
mattress in all directions. The ends of the coils are secured to the
ticking by means of metal thimbles, inside of which are pieces of wire
gauze, to prevent insects getting in, but which admit air freely. The
cost of the ventilators is small, and they will last as long as any
mattress. They can be applied to any bed at small expense.

This invention was patented through the Scientific American Patent
Agency, January 10, 1871. The right to manufacture will be disposed
of in any part of the country. Further information can be obtained by
addressing the proprietors, Barnes & Allen, Hoosick Falls, N. Y.

* * * * *

The third annual exhibition of the National Photographic Association
takes place at Horticultural Hall, Philadelphia, June 6, 1871. Prof.
Morton is to deliver two lectures on Light.

* * * * *

A SCIENTIFIC AND TECHNICAL AWAKENING.

Our English cotemporary, _Engineering_, appears to have seriously
exercised itself in the perusal of our good-natured article
on "English and American Scientific and Mechanical Engineering
Journalism," which appeared in the SCIENTIFIC AMERICAN, February
4th; at least, we so judge from the tenor of an article in response
thereto, covering a full page of that journal. The article in question
is a curiosity in literature. It deserves a much wider circulation
than _Engineering_ can give it, and we would gladly transfer it to our
columns, but for its exceeding length--a serious fault generally, not
only with _Engineering's_ articles, but most other technical journals
published in Eng