Year: 1872

The lungs after a full inspiration,
contain 30 cubic inches of air, thus
making their inner surface equal to 40


square feet, nearly thirty times greater


than the surface of the body; and theso


organs on an average, make from 2S,-


600 to 10000 respirations in twenty
four hours.


Sledge hammers made from cast


steel are superior to those made with


iron and faced with steel. They cost


about twice as much as the latter,


but will perform fully four times the


amount of work without requiring to


be dressed.


WATERPROOF LEATHER.-A patent


is now being worked by which leather


for the sides of boots and shoes is rem


dered impervious to wet and damp by


exhausting the air from the pores of


the leather, and filling them up with a


substance which unites with and ad-


heres to the fiber, thereby strengthen


ing without imparing the elasticity of


the material. When asphalte pave
ment becomes general, it will be pos
sible to shoe horses with a material as
hard as asphalte itself, and which will
prevent them slipping.


MARVEL OF THE MICRosCoPE.-A
beautiful and easily produced exhibi-
ton of crystal formation may be seen
under the microscope as follows: Upon
slip of glass, place drop of liquid
chloride of gold or nitrate of silver,
with a particle Of zinc in the gold and
copper in the silver. y growth of eX-
quisite gold or silver ferns will vegetate
under the Observers delighted eye.


Five eighth inch octagon steel is the
best for making punches, cold chisels,
or drills; one and a quarter inches
square is the bestsize to use for making
chisels. To make good sized tiatting
hammer, you will require about six
inches of one and half inches square
steel. This will also make you as
heavy hand hammer as any ordinary
man ought to use. If you make but
one hammer let it be of the face and
ball pattern.


According to the London architect,
NJ. Gustave Dore is about to challenge
the opinion of the world of art ON a
grand scale. He has just finished q
picture thirty feet long by twenty
wide, at which he has been working
pretty constantly for four years. The
subject of this large composition is
4" Christ Leaving the Temple" and
it contains about four hundred figures.
This picture is to be shown for a few days
in the painters studio in Paris, and to
be sent to London for public exhibi-
ton.


GERMS OF DISEASE Not DESTRUCTI-
BILE BY HEAT.-As the result of eX-
periments on the destruction of low
forms of life by heat, DIR. Grace Calvert
that the germs o. disease
will withstand a temperature of 300
degrees Fahrenheit. Exposure to such
a heat as this Injuries the fibres of
all kinds of cloth so seriously
that they are unfit for further Use. 1t
is therefore evident that the mere
agency of heat cannot be depended up
on for the destruction of the germs of
corpuscles attached to the clothing of
persons who have suffered from any
contagious disease.


Metallic soap in linseed-oil is highly
for coating canvass for
wagon covers, tents, etc., as being not
only impermeable to moisture, but re-
manning pliable for long time withOt
breaking. 1t can be made with little
expense, as follows: Soft soap is to be
dissolved in hot water, and solution
Of copperas (sulphate of irOnls added.
The sulphuric acid combines with the
potash of the soap, and oxide of iron Is
precipitated with the fatty acid rs IN
soluble irOn-sOap. This is washed and
dried and mixed with linssed-Oil. The
addition of dissolved India-rubber TO
the oil greatly improves the plant.