so high that
they could not see them.
_Developpant du Gaz._ That is, in plain English, _burning more straw_;
for tho' there is a little Mystery made, concerning the kind of Air
with which the Balloon is filled, I conceive it to be nothing more than
hot Smoke or common Air rarify'd, tho' in this I may be mistaken.
_Aiant encor dans leur Galerie les deux tiers de leur
Approvisionement._ That is their Provision of Straw; of which they
carried up a great Quantity. It was well that in the hurry of so
hazardous an Experiment, the Flame did not happen by any accidental
Mismanagement to lay hold of this Straw; tho' each had a Bucket of
Water by him, by Way of Precaution.
One of these courageous Philosophers, the Marquis d'Arlandes, did me
the honour to call upon me in the Evening after the Experiment, with
Mr. Montgolfier the very ingenious Inventor. I was happy to see him
safe. He informed me that they lit gently without the least Shock, and
the Balloon was very little damaged.
This Method of filling the Balloon with hot Air is cheap and
expeditious, and it is supposed may be sufficient for certain purposes,
such as elevating an Engineer to take a View of an Enemy's Army, Works,
&c. conveying Intelligence into, or out of a besieged Town, giving
Signals to distant Places, or the like.
The other Method of filling a Balloon with permanently elastic
inflammable Air, and then closing it is a tedious Operation, and
very expensive; Yet we are to have one of that kind sent up in a few
Days. It is a Globe of 26 feet diameter. The Gores that compose it
are red and white Silk, so that it makes a beautiful appearance. A
very handsome triumphal Car will be suspended to it, in which Mess^rs.
Robert, two Brothers, very ingenious Men, who have made it in concert
with Mr. Charles propose to go up. There is room in this Car for a
little Table to be placed between them, on which they can write and
keep their Journal, that is take Notes of every thing they observe, the
State of their Thermometer, Barometer, Hygrometer, &c which they will
have more Leisure to do than the others, having no fire to take Care
of. They say they have a contrivance which will enable them to descend
at Pleasure. I know not what it is. But the Expence of this Machine,
Filling included, will exceed, it is said, 10,000 Livres.
This Balloon of only 26 feet diameter being filled with Air ten times
lighter than common
_ _The Editor was therefore prevailed upon to commit such extracts of letters, and other detach'd pieces as were in his hands to the press, without waiting for the ingenious author's permission so to do; and this was done with the less hesitation, as it was apprehended the author's engagements in other affairs, would scarce afford him leisure to give the publick his reflections and experiments on the subject, finish'd with that care and precision, of which the treatise before us shews he is alike studious and capable.Page 1
reflections, to a probable cause of those phaenomena, which are at once the most awful, and, hitherto, accounted for with the least verisimilitude.Page 5
EXPERIMENT XI.Page 12
In this experiment the bottles are totally discharged, or the equilibrium within them restored.Page 14
--And this restitution cannot be made through the substance of the glass, but must be done by a non-electric communication formed without, from surface to surface.Page 15
Gild likewise the inner edge of the back of the frame all round except the top part, and form a communication between that gilding and the gilding behind the glass: then put in the board, and that side is finished.Page 18
On the edge of the wheel is a small leaden bullet communicating by a wire with the gilding of the _upper_ surface of the wheel; and about six inches from it is another bullet communicating in like manner with the _under_ surface.Page 20
A dry cake of ice, or an icicle held between two in a circle, likewise prevents the shock; which one would not expect, as water conducts it so perfectly well.Page 23
To shew this by an easy experiment.Page 27
It is safer to be in the open field for another reason.Page 31
If a piece of common matter be supposed intirely free from electrical matter, and a single particle of the latter be brought nigh, 'twill be attracted and enter the body, and take place in the center, or where the attraction is every way equal.Page 32
Take away these atmospheres by touching the balls, and leave them in their natural state: then, having fixed a stick of sealing wax to the middle of the vial to hold it by, apply the wire to A, at the same time the coating touches B.Page 33
has the line A, E, for its basis.Page 35
Attempt to draw off the electricity with a blunt body, as a bolt of iron round at the end and smooth (a silversmith's iron punch, inch-thick, is what I use) and you must bring it within the distance of three inches before you can do it, and then it is done with a stroke and crack.Page 43
[Illustration] 33.Page 48
For though the effluvia of cinnamon, and the electrical fluid should mix within the globe, they would never come out together through the pores of the glass, and so go to the prime conductor; for the electrical fluid itself cannot come through; and the prime conductor is always supply'd from the cushion, and that from the floor.Page 52
Price 3s.Page 53