The Complete Works in Philosophy, Politics and Morals of the late Dr. Benjamin Franklin, Vol. 2 [of 3]

By Benjamin Franklin

Page 197

obliged
to run frequently to the fire to warm themselves: and to physicians
to say, how much healthier thick-built towns and cities will be,
now half-suffocated with sulphury smoke, when so much less of that
smoke shall be made, and the air breathed by the inhabitants be
consequently so much purer. These things it will suffice just to have
mentioned; let us proceed to give some necessary directions to the
workman who is to fix or set up these fire-places.


_Directions to the Bricklayer._

The chimney being first well swept and cleansed from soot, &c.
lay the bottom plate down on the hearth, in the place where the
fire-place is to stand, which may be as forward as the hearth will
allow. Chalk a line from one of its back corners round the plate
to the other corner, that you may afterwards know its place when
you come to fix it; and from those corners, two parallel lines to
the back of the chimney: make marks also on each side, that you
may know where the partition is to stand, which is to prevent any
communication between the air and smoke. Then, removing the plate,
make a hollow under it and beyond it, by taking up as many of the
bricks or tiles as you can, within your chalked lines, quite to
the chimney-back. Dig out six or eight inches deep of the earth
or rubbish, all the breadth and length of your hollow; then make
a passage of four inches square (if the place will allow so much)
leading from the hollow to some place communicating with the outer
air; by _outer air_ we mean air without the room you intend to warm.
This passage may be made to enter your hollow on either side, or in
the fore part, just as you find most convenient, the circumstances
of your chimney considered. If the fire-place is to be put up in
a chamber, you may have this communication of outer air from the
stair-case; or sometimes more easily from between the chamber floor,
and the ceiling of the lower room, making only a small hole in the
wall of the house entering the space betwixt those two joists with
which your air-passage in the hearth communicates. If this air
passage be so situated as that mice may enter it, and nestle in the
hollow, a little grate of wire will keep them out. This passage
being made, and, if it runs under any part of the earth, tiled
over securely, you may proceed to raise your false back. This may
be of four inches or two

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Text Comparison with Experiments and Observations on Electricity Made at Philadelphia in America

Page 0
* * * * * * _LONDON_: Printed and sold by E.
Page 5
in your hand.
Page 6
The closer the contact between the shoulder of the wire, and the gold at one end of the line, and between the bottom of the bottle and the gold at the other end, the better the experiment succeeds.
Page 9
And we daily in our experiments electrise bodies _plus_ or _minus_ as we think proper.
Page 10
Give him the electrised bottle in his hand.
Page 11
TO Mr PETER COLLINSON, F.
Page 17
a quire of paper is thought good armour against the push of a sword or even against a pistol bullet) and the crack is exceeding loud.
Page 19
Part of the gilding torn off, is also found forcibly driven into the hole made in the paper by the stroke.
Page 22
12.
Page 23
The sun supplies (or seems to supply) common fire to all vapours, whether raised from earth or sea.
Page 24
Hence the continual storms of rain, thunder, and lightning on the east-side of the _Andes_, which running north and south, and being vastly high, intercept all the clouds brought against them from the _Atlantic_ ocean by the trade winds, and oblige them to deposite their waters, by which the vast rivers _Amazons_, _La Plata_, and _Oroonoko_ are formed, which return the water into the same sea, after.
Page 26
36.
Page 33
Now if you would draw off this atmosphere with any blunt smooth body, and approach the middle of the side A, B, you must come very near before the force of your attracter exceeds the force or power with which that side holds its atmosphere.
Page 34
But points have a property, by which they _draw on_ as well as _throw off_ the electrical fluid, at greater distances than blunt bodies can.
Page 37
) big enough to contain a man and an electrical stand.
Page 38
The biggest animal we have yet killed or try'd to kill with the electrical stroke, was a well-grown pullet.
Page 46
[12] If the tube be exhausted of air, a non electric lining in contact with the wire is not necessary; for _in vacuo_, the electrical fire will fly freely from the inner surface, without a non-electric conductor: but air resists its motion; for being itself an electric _per se_, it does not attract it, having already its quantity.
Page 47
from the mutual repulsion of its particles, tends to dissipation, and would immediately dissipate _in vacuo_.
Page 51
_ BOOKS Printed and Sold by EDWARD CAVE, at St.
Page 54
[12] See farther experiments, s 15.