~ 
2290 
which I impofed on myfelf forty years ago, 
of calculating all the eclipfes of the fun 
and ftars, which have been obferved ; and 
from which afironomers, till that time, 
had neglected to draw any conclufians, on 
account of the length of the balemiations. 
7 have corrected the va Re of Rome, 
Middleburg, and the new city of “Wathing- 
ton in Wises: 
M. Leduc, of Sermonetta, Gaetani, 
-'and M. Conti have favoured me with ob- 
fervations from Rome. M. Ciccolini has 
fent fome from Florence; and the very 
day that the King of Etruria came to the 
Inftitute, I had the pleafure of prefenting 
him with an accurate determination of the 
longitude of Florence, which had never 
been accurately afcertained, notwithfiand- 
ing the celebrity of that capital, and the 
great number of diftinguifhed charaSers 
it has produced. 
M. Kautfch, at Leutomifchel, in Bo- 
hemia, has completed an immenfe work 
on the eclipfes of the fun. | He has calcu- 
lated them for the whole nineteenth cen- 
tury, with diagrams by which may be 
feen the particular circumftances under 
which they will appear in all countries 
_where they are vifible, in the fame manner 
as has been donein our Ephemeris, from the 
year 1750 to 1800, and in the Connoifjance 
des Temps, by the affiduity of Citizen 
Duvancel. I fhould have rejoiced to have 
had the means of publithing this work of 
M. Kautfch, whofe zeal and abilities 
claim our higheft praife. 
Citizen Goudin, who has alfo publifh- 
ed an analytical method of calculating 
eclipfes, has applied it to the eclipfe of 
1847, which will be the moft confiderable 
that can happen during this century. 
His calculations are Very much detailed, 
snd are applied to the whole furface of the 
earth. 
The conjunctions of the planets among 
themfelves do not imtereft aftronomers ; 
but they are fomtimes attended to by the 
public, efpecially when connected wita 
other events. ‘Thus Citizen Meffier has 
thought it worth his while to remark 
that the cannon announced the happy fe 
turn of peace, by the figning of the pre- 
liminaries, on the 3d of nein g 
when the Moon, Venus, Jupiter, and £a- 
furn were near the beautiful flar ‘in the 
Lion’s Heart. 
Weare no longer under the influence of 
opinions which ‘attach to thefe kind of 
circumfiances any importance; but, in 
the year 1186, aftronomers foretold terri- 
ble revolutions, 2 In confequence of the con- 
The Hiftory of Aferonomy, by C. Lalande, 
‘nature, on the fame 
[ April 1, 
junétion of all the planets. I engaged 
Citizen Flaugergues to calculate exaétly 
when this happened by our new tables, 
and he found that, on the rsth of Sep- 
tember at two minutes after five, all the 
planets were between fix figus, and fix 
figns and ten degrees of longitude. 
Thefe conjunctions of ail the planets 
are not very accurate; but thofe which 
fhould be perfedily exact would be in- 
calculable. I have afcertained that the 
interval between two conjunctions of tnis 
day, would be more 
than feventeen thoufand millions of mil- 
lions of years. ‘What would be the fpace. 
of time, if the accuracy were determined 
to hours and minutes? 
The tables relating to the planet Mars 
‘have hitherto been lee accurate than thefe 
‘belonging te the other planets. 
Citizen 
Lefrancais has been engaged: in this bufi- 
nefs during the laft fix months; he has 
calculated all the obfervations ; 3 he has car- 
ried his accuracy to tenths of feconds ; 
and he. has, at léngth, prepared a fet of 
tables for Mars which will leave but little 
to be defired, and which will appear in the 
Connoiffance des Ti emps, for the Year 1804. 
I have feen with much pleafure my imme- 
diate fucceffor and highly efteemed pupil 
purfuing the work which Citizen Lemon- 
nier, my mafter, engaged me to under- 
take fifty years ago, in conformity to the 
example of Tycho Brahe, who began his 
refearches. on the planet Mars, and who 
put Kepler into the way of his difcoveries 
by means of the fame planet. He is going 
to underteke tables for the planet Venus, 
with a view of keeping an account of its 
inregwiarifies. 
As for Saturn, an error of + 1” has 
been found in its longitude, &—o" in 
latitude. Citizeh Delambre has made 
many attempts to get rid ef the error of 
30" in the tables of Jupiter; but it was 
found extended to the obfervations made 
fixty yearsago. Thus it will be neceflary 
to feek the caufes of i its in the theory, and 
in cer tain new inequalities. 
Citizen Bouvard has finithed thesealeu-- 
lations of the difturbing forces of the 
planets, each as acted upon by all the 
others, according to the theory of Citizen’ 
Laplace; frem thefe tables we may ex;ect 
the greateft accuracy. Citizen Burek- 
hardt has made an analytical and numeri- 
cal calculation of the limits of the fifth or- ° 
der, of which no account had been kept, 
owing to-the length of the calculations. 
Citizen Chabrole has calculated fome 
obfervations of the fun; and finds that 
: g"! are 
