1799 | 
which is preffed out, and mixed by the 
tobacconifts with four or five times its 
quantity of cold water, and fold in this 
ftate, as a liquor for deftroying bugs. It 
is in faét, nothing more than a ftreng in- 
fufion of tobacco in water; and may be . 
made equally well by adding water to any 
kind of tobacco. 
The following extraé&t from a letter 
from the celebrated Montgolfier, to one of 
his aeroftatic friends, dated March 24th, 
1789, and given in the latt number of the 
Azxnales de Chimie, will fhew.that this in- 
genious philofopher was the firft that con- 
ftructed the Parachute, am inftrument for 
defcending from great heights, which is now 
brought toconfiderable pertection inFrance. 
<¢ An idea has occurred to me, which I will © 
immediately communicate to you, as per- 
haps you may derive fome advantage from 
it in cafe of an accidental {eparation from 
your balloon, when in: the air. It is to 
make a parachute, by means of which you 
may come down from any height without 
danger or inconvenience. ‘The principle 
on which I reafon is the following. A 
mafs of matter, when at reft, cannot be 
moved without being ftruck by another 
ma({s in motion; and the motion acquired 
by the former, is at the expence of that-of 
the latter. Thus, a hundred weight of 
matter, when at reft, if it is {et in motion 
by an equal quantity of matter, moving at 
the rate of twenty feet in a fecond, the 
united maffes will only move at the rate of 
ten feet ina fecond. Ifthe body in mo- 
tion only weighs ten pounds, the whole will 
proceed only at the rate of two feet in a 
fecond. Hence, if eight hundred weight of 
air be inclofed in a bag among the clouds, 
and the bag, with a man attached to it, 
only weigh two hundred weight, the fall 
of the whole will be retarded three-fourths 
of its velocity. Ifto this be added the re- 
fiftance of the air againft the falling body, 
‘you fee thata manmayde/cend veryagreeably 
even from the clouds; and fo, if you pleale, 
“you. may fhower down an army into a 
town, as Mr. Brante and I did a few fheep, 
in the experiment which we made yetter- 
day afternoon. For this purpole we made 
a filk bag, from feven to eight feet in dia- 
meter,and of the ferm of a hemiiphere. 
We tied twelve cords, each {even feet long, 
to the margin of thd bag, at equal diftances 
from each other; and to the other end 
we faftened a ftrong ozier bafket, and be- 
neath the bafket, we fixed four hogs blad- 
ders by means of anépkin. A fheep was 
put in the bafket and the whole apparatus 
thus loaded, weighed fifty pounds. We 
took this to the top of the higheft towerin 
Avignon, which is ahout a hundred eet 
Montary Mag. Ne. Lil. 
Literary and Philofiphical- Intelligence. " 
893 
from the ftreet, and I launched it o7, with 
all my ftrength, to make it clear the wall. 
For the firft fifty feet, the fall was very 
rapid; but the parachute being then fully 
expanded, the defcent became very gradual, 
fo that the crowdof f{peétators ran underneath 
to receive it. As ioonas the bafket touched 
the ground, the fheep took to his heels with 
all his might. He was brought back and 
made much of by the crowd, and taken up 
again to the tower, and made to defeend 
again unhurt. ‘This voyage was repeated 
fix times, and the fheep was not in the 
‘leaft degree injured by any one of them. 
From this experiment it appears, that a 
hemifphere of filk, twenty feet in diameter, 
would enable a man to defcend with fafety 
from the clouds; and I would advife you 
to furnifh your balloon with one of them. 
Seventy-five ells would be fufficient for this 
purpofe, which, at fifty-five fo/s the ell, 
would not make the whole machine come _ 
to more than ten /ouis.”’ 
LALANDE writes to M. yon Zach. 
Paris 25th July 1799. 
folftice we obferved here, with the greateft 
attention, the obliquity of the ecliptic. 
From feven feries of oblervations, the me- 
dium refult was 23° 28’ 5,5 ; that iss 
7" more than in my Tables. De Lambre 
found it to be 4” lefs: however, we can- 
not comprehend whence this -difference 
could arile ; for Mechain, from ninety- 
eight obfervations, found it the fame as 
we had done.” ; 
In M. von Zacu’s Tab. Mot. fol. {. 1x. 
the medium obliquity of the ecliptic for 
the 21ft of June 1799 is=ez3 23” 3°4)65, 
and confequently the difference from La- 
lande’s obfervation is only 1", 85. If De 
Lambre’s determination were the true one, 
the obliquity of M. von Zach’s Tables 
correfponds with it to within ,3. of a ie-" 
cond. | 
Vinal, of Mirepoix, has fent Lalande 
a valuable Catalogue of 3887 fouttiern 
ftars, betwixt the 35th and asth degree of 
fouth declination. Thefe ftars the latter 
intends to infert in his Hiffoire Celee, of 
which 440 pages are already printed. The 
progrefs of the work is much retarded by 
the author's being under the neceffity of 
fending the proof. theets of Darquier’s Ob- 
x 
fervations as far as Touloufe.—Lelande’s — 
Bibliographie Aflronomique is printed as 
far as the 184th page, year 1622. 
ExtraG of a letter from LeoroLtp von 
Bucu, to M. wou Zach, dated Paris, 
22d Fuly 1799+ 
As Monte Cavo (Mons Albanus), the 
highelt mountain in the vicinity of Rome, 
the extenfive profpects from which may be 
oe & reckoned 
«* At the prefent . 
—t- 
ee —— 
