1804. | 
the navy. Baren Von Zach, in his 
oblervations, has found a fingular a- 
greement: the refults will appear in his 
journal. Thirty obfervations, made 
indifcriminately, gave him the fame fe- 
cond’ as three hundred: he meafured a 
bafe of a thoufand toifes to within an 
inch. Such extenfive operations have 
never been conducted with fo much exakt- 
nefs, 
Mefirs. Goldbach and Seyffert have de- | 
termined fix places of the electorate of 
Saxony, during an aftronomical tour, un- 
dertaken for the purpofe of obferving the 
fignals by fire, which baron Von Zach 
made on the Brocken. Tf fhall mention 
only the two principal towns: Eifleben, 
§1° 32! 30! and 8’ 45, in time to the 
welt of the meridian of Drefden; Merfe- 
Ding Suop aa: 43') \andyi")/29\'9.ho the 
weft of the meridian of Leipzig. The 
Jaft determination is exceedingly exact, 
having been verified by the refult of a tri- 
gonometrical meafurement begun by M, 
Goldbach, and for which he had been 
collecting for feveral years the beft inftru- 
ments; namely, a toife made by Lenoir ; 
a repeating circle by the fame artift; a 
fextant by Ramfden; a circle by Bau- 
mann; a ftcel chain of fify feet, con- 
ftructed like that made by Ram{den for 
general Roy’s meafurement; a clock by 
Syffert, and a travelling time-piece that 
beats half feconds. It is much to be re- 
gretted, that fo zealous and able an ama- 
teur as M. Goldbach, can devate only 
, a fmall part of his time to aftronomy. 
The chronometer he employed in this 
journey, was made by M. Syffert. 
The hiftory of meteorology is every 
year connected with that of aftronomy ; 
but this year meteorology has furnifhed 
remarkable phenomena: the equinoctial 
winds have been litle felt, and the au- 
_tumnal rains were very weak. 
The tide at the end of March ought 
to have been exceedingly ftrong, accord- 
ing to the theory of Laplace. Traulée, 
of Abbeville, paid attention to this cb- 
ject at that place, and fent curious obfer- 
vations to the Board ef Longitude. M. 
Maignon obferved the tides at Breft: 
precautions had been taken; and indeed 
if the wef wind had been ftrong, we 
fhould have had inundations. We requett. 
from every quarter obiervations on the 
tides ; and during my journeys to Cher- 
burg and Oftend, I had the pleafure this 
year of feeing that fcales of the tides are 
preparing. I received obfervations from 
M, Caron, a lieutenant in the navy at 
Hiftory of Afironomy for the Year 1803. 
31 
Oftend ; and I have been a witnefs to his 
alfiduity and corteétnefs. 
The thermometer this year was only 
once at 12° 30’ of ‘cold, or 43° of my 
new thermometer. The heat was of as 
long contiauance as it was extraordinary 5 
the drought lafted three months and a 
half, yet the heat was only 29° 30’, or 
37° of my new thermometer; while in 
77535 1765, and 1793, it was at 42% 3; 
but the duration of it. oceafioned one of 
the hotteft fummers we have had for a 
century, If I fpeak of my new thermo- 
meter, it is becaufe the divifion I have 
adopted, which is more philofophical, 
more natural, frople, and more conve- 
nient, contains numbers eafier to be re- 
tained: every body {peaks of 49 and ao; 
and it happens, by a fingular chance, that 
thefe numbers 30 and 4o are thofe which 
exptefs the moderate and fcorching fum- 
mers, the mild and fevere winters, the 
degrees of heat and of cold. Thefe num_ 
bers, hitherto decried, will be ennobled 
by becoming the key of the thermometric 
fcience. Our ableft artift for this kind of 
inftruments, M. Mofly, known by his 
excellent and accurate works, has under- 
taken to conftruét my thermometers, and 
flatters himfelf he fhall be able to extend 
the ufe cf them. 
M. Thulis has fent us obfervations of 
the barometer, which give for the meas 
height, at the borders of the fea, 28 
inches 2°8 lines, inftead of 2:2 lines, 
which £ found as the mean of feveral de- 
terminations. M. Burckhardt found from 
2°2 lines to 2:8*. ‘There ftiil remains an* 
uncertainty of half a line, in regard to this 
fundamental determination: of meteorolo- 
gy. It exifts even at Paris; for the ther- 
mometers at the obfervatory indicate half 
a line more than that of M. Fleurieu and 
mine, which were made with the preatet 
care. 
The water of the Seine funk lower than 
ever before obferved. It has been feen 
lower than the zero at the Pont de la 
Tourne!le, or the low water of 1719. In 
1731, September 23d, it was 54. inches ; 
in 1742, between the 7th and sgth of 
September, 3 inches; in 1753, from Sep- 
tember 28th to October rft, 1.inch; in 
1766, December 5:h, 2 inches; in 1757, 
January rt, 34 inches; in 1778, Septem:-: 
ber 8th, 4 inches; in 1800, Auguft 8th, 
64 inches ; and in 1803, from the 12th to 
the rsth of September, it fell to 10 inches, 
* Counoilfance des Temps, an 73, p. 349. 
accord= 
