eertain ftones called ‘our iG 
Mount St. Gothard, © or i object to 
enquire how far the Pic conf dered a8 
a character of the ftones, may ferve to. 
determine the nature of them... 
Laftly, fome new ex criments of Citi- 
zen VAUQUELIN, ont ered lead of Si- 
beria, and on a new earth which he has 
found in the beril, or aigue-marine, are 
the ground- work. on a memoir which he 
read in this fitting. 
MATHEMATICAL PART. 
Cittizn FLAUGERGUE, an affociate 
member, communicated a number of ob- 
fervations on general phylics, together 
with a table calculated by him, of the 
fymmetrical folids which may beinicribed 
in a fphere. 
Citizen LaLanDE read the defcription 
of a zodiac iets « on ate portal of the 
church at Strafburgh. He has compared 
it with thofe of Notre Dame at Paris, and 
of St. Dennis, and with that which is 
feen.on fome very beautiful mais books in 
the Brbhotheque Nationale. We explains 
the caufe of fome differences in the figns 
and in the tables of agricultural opeugs, 
tions which accompany each iign. 
The fame author prefented, the printed 

273 
and Ace membranes of fifhes. It is fe- 
cured from the aétion of moifure by lin- 
feed oil rendered ficcative. 
In another printed memoir, the fame 
author points out the advantage of ora 
phical methods for determining the longi- 
tudes at fea, by the diftances of the moon 
‘ from the fun and ftars. It is to be wifhed 
that mathematical knowledge were fuik- 
ciently cultivated in the marine to fuper- 
fede’ the® neceility, of the graphical’ me- 
theds. © Till this point be attained, Ci- 
tizen RocHuon has affifted navigators 
with two charts and a table, by’ the 
help: of which they’ may find, alnolt 
without calculation, the true diteict: ey by 
the moon from the fan, according to the 
obferved apparent citanes and {0 by this 
graphical method obtain t 
the vefiel. 
Citizen La PLac 
the fécular equations ‘of the motion of the 
moon, of its apogee, and’ of its nodes. 
By comperiis the modern obfervations 
with thofe of the Chaldeans and Aira 
Bias, aftronomers. have acquired the ac- 
celeration of the mean motion of the 
moon; gbut no vafiation has been ful 
pected i in tht mean motions of thenedes and 
the My Salata 
E read a memoir OR 
notice of the Hiftory of “Aftronomy for 
the year V. He there gives an account 
_ of the difcovery of joey new fatellites of 
_ the planet Herichel, and of the progrefs 
a which Citizen LEFRANCOIS has made in 
4 pe. work of the defcription of the 
ivens ;, the number of ftars which he 
of the apogre. Citizen La 'Pracx, after 
having fotnd the caule of the fecular 
equation of the lunar pe aS has dif- 
covered tha the motion of the nodes and 
that of ‘th; _ apogee are retarded, while 
that of th¢-moon is accelerated ; from 
whence itrdults, that the feculan motion 
has already obferved, is 44,000. Healfo 
~ prefented a table for regulating. clocks by 
mean time ; this table is alfo found in 
e new edition of the Treatifes on the 
Sphere and Calendar, by RrvarD, which 
Citizen Lalande has juft publithed. 
Citizen THuULIS communicated the 
meteorological obfervations which he has 
made at Marfeilles, for a number of years 
patt.: 
-»Citizen Prony gave arm account of the 
‘Bbours of dhe commifiton appointed by. 
the Infitute, to make inquiry inte the 
theans proper to. be adopted, to faye from 
the flames perfons who may be fhut up in 
a houfe on fire. 
Citizen Rocuow read a memoir on the 
preparation and ufe of metallic gauzes, 

rom 
- covered with a folid tranfparent coating. | 
Thefe gauzes may be fubftituted for horn 
in Janthorns, in the conitructions of fanals 
or lights for thip magazines, for entre- 
Ponts, and for fighting. The model of 
the fanal was laid befere the Inftitute. 
~» The fubftance which furnifhes the coat- 
"ing, is fize, parchment glue, air-bladders, 
uw 
4 
\ 
. ' 
=, On the ath Nivofe laff, 
of thé anomaly of our lunar tables ought — 
to be augnented 85 minutes, and that 
from this jime the anomaly fhould be 
augmented | minutes in thof tables, if 
we would leep them in that degree of 
precifion wiich they had about r750 
Citizen LA Piace then febmits ioe ana- 
fyfis the refftance of the ether, and the 
fuccefive trnfmiffion of gravity. Thee 
two hypothtic caufes, contewved with 2 
view to exphm the variations of the lunar 
motion, hn its real caufe was not 
known, dojot produce any fenfible al- 
teration intlie motions of the nodes and 
of the apoze; which is fufficient, ob- 
ferves LA P\ACE, to exclude them, as the 
retardation }f thoie motions is clearly 
thewn from he obfervations. 
quarters aff¢ one o’clock, Citizen Dan? 
GOS, an allciate ynember, faw on the 
dife of thejun, <a black point, w 
nutes pafton, its diftance from the fun’s 
edge had cofide rably diminifhed, 
motion isd fe ZEN D 
a 
Dancos to think 
thae 
pr” 
about three . 
This* 
Which - 
he took at rt fay afpot. At 58 mi- 
