3799-1] 
From the end of Nivofe (the middle of 
January) DELAMBRE, impatient to 
commence his painful labours, went to 
prepare the bafe from Lieurfaint to Me- 
lun, to overfee the finifhing ofthe wooden 
pyramids which are feventy feet in height, 
and to meafure the angles; the cold and 
‘rain did not prevent his operations. 
On the 6th Ventdfe (February 24th) 
he had already finifhed feven {tations for 
the angles. at the bafe ; three men had 
been employed during fix weeks in lopping 
the branches of fix or feven hundred trees 
on the high road, which intercepted the 
fight of the fignals. 
The 28th Germinal, (April 17th) 
he fet out to go and mealure the bate 
from Melun to Lieurfaint; a painful la- 
bour, in which fuch a ftri&t attention was 
required, that with the help of feven per- 
fons they could only meafure one hundred 
and eighty toifes per day. 
The rsth Prairial (3d June) the mea- 
fure of the bafe of three leagues, 6075 
toifes, was finifhed at Liecurfaint. 
‘Vhe 12th Meflidor (June 30th) citizen 
DELAMBRE fet out to go and meafure 
the bafe of Perpignan ; it was terminat- 
ed onthe firft complementary day. At 
the fame time citizen MECHAIN termi- 
nated his triangles between Rodez and 
Carcaffone, after having furmounted 
ficknefles, obftructions and delays of 
every kind; More unfortunate, and 
lefS robuft than his colleague, his zeal 
only ferved to agitate him the more. 
Atlength, on the 27th of this month, 
Frimaire (November 17th), they arriv- 
ed at Paris ; after. having finifhed the cal- 
culations, in which they found the two 
bafes to correfpond exa&tly. Thus this 
immenfe undertaking, of a new admea- 
furement of the earth, commenced in 
thementh of June, 1792, by our two 
_ moft fkilful aftronomers, is at length ter- 
minated, and we fhall foon have the fo 
much wifhed-for refults relative to the 
magnitude and fieure.of the earth, and 
perhaps its irregularities, Our two 
fkilful aftronomers with moreover to de- 
termine once again the latitude of Paris, 
which I had fixed at 48 deg. 50 min. 
15fec. three years ago, after more than 
two hundred obfervations made with the 
circle invented by citizen Borba, dimi- 
nifhing by one fecond the refraction of 
Bradley, which is the total of any re- 
maining uncertainty. tj G4 
The enumeration of the ftars, begun 
in 1798, is brought to 47,000, and we 
do not want 2000 to have completed the 
tour of the heavens as far as the infe- 
Baths 
Hiftory of Aftronomy for 1798. 
203 
rior tropic: there. will be: s0j000, by 
taking two degrees beyond that, Citizen 
Le Francois is difpofed to, finifh his 
labour this winter, and already he is en- 
joying the refults of it. Comets are at 
prefent the only part of aftronomy which 
is but little advanced: it is that which 
the aftronomers are now going to be oc- 
cupied in. I have not been backward to 
prepare for them the only affiftance which 
they wanted, by giving them pofitions of 
ftars in all parts of the heavens: they 
will never be able to obferve comets 
without recurring to our 50,000 ftars, 
where they will be fure to find whatever 
they candefire. Ihave had experience of 
them tor many years. 
But a great and important work mutt 
have detrators; they will urge the ex- 
pediency of having fewer ftars, and of 
adjufting them with a greater degree of 
precifion, ‘Thefe perfons are miltaken; 
it is the great number of {tars which ac- 
complithes the neceflary object of this la- 
bour; a greater exactitude is of little 
ufe at prefent, and will be fo for a long 
time to come. Comets are only obferved 
at thirty feconds, and yet many wrth to 
have the pofitions of ftars at a fecond: 
this is an evident inconfequenceand a ma- 
nifeft impoffibility. We have therefore 
dene all that was neceflary to be done; 
and I think myfelf happy in having ter- 
minated my career, by procuring to aftra- 
homy a monument which, from its im- 
menfity, might have been judged im- 
pofible. Tojudge of the utility of the 
labour of Citizen Le FRANcoIs, it-may 
fuflice to fay, that in a zone of three 
hours, having two degrees of breadth, 
he has had thirty new ftars of the fifth or 
fixth magnitude, and from fix to feven, 
and only three of them that were known. 
Dec. 10, 1789, of ane kundred ftars, 
thirteen of which were of the fixth mag- 
nitude, there was only a. fingle one 
known; the other twelve were. entirely 
new to us.. This fuffices to thew how 
far we are from being thoroughly ac- 
quainted with the ftarry heaven. It is 
for this. reafon that, as {oon as I was 
able to procare a good \nftrument,: I 
have been fomuch engaged ij this labour. 
M. HERsCHEL has alfo pndertaken a 
review of the heavens with his 20 feet te- 
lefcope; but itis in ordef to difcover ne- 
bulous {pots or objects difficult to ‘be 
feen, Our labsuf is more important, AS 
it furnifhes exa& pofitions of all the ftars 
which aftronomers can make ue of, 
HERSCHEL only obferves things ‘invi- 
fible; and aftronomers have reed of ob- 
jects 
