306 



Hijlory of JJlfonomy far 1 80-i. 



[Nor. \i 



For the Monthly Magazine. 



HisTor.Y 0/ ASTRONOMY /ar 1804 — 



By JtROME Dd. LA LANDE. 



\^C:oiicluJeJftomp.z\T of our Inft Number.'] 



THE 1 .bouis of the Regiftry of Linds 

 ill France are actively continued ; 

 there are 2000 perfons employed in the 

 idS departments. 



M. But read to the Tnftitute a Memoir 

 on the loadrtonc, in which, conformably to 

 the oblervations of M. Humboldt, he 

 fiipports the hyputhefis of a magnetic mafs 

 Cfjated neaily at the centre of the earth, 

 towaids the 79th degree cf htitude, to 

 the north of Amer.ca ; and he thence de- 

 duces a formula rcprefenting the iiiclina- 

 lion of the needle in different latitudes 

 and the in-eniity of the magnetic power. 

 It atf dsthe means of nearly alcertaining 

 th.e i nsiiu'.e and latitude of a country 

 wheie currents or' f.gs render navigatots 

 liable todan^irous errors. 



Tietein.elh of this year have been 

 both ex riordinary and f.tquent. Jhat 

 of tht 6th June committed gr<:at rav>ges 

 a> Palis and to the ditlance of one hun- 

 dred ieagu s eaft and fouth ; a> other, on 

 the 7ih,''K.olc place in Swii7.tr!and ; the 

 , rh in Styria ; ihe lyth at Mont-uban ; 

 the ill July in the department of Landes 

 and in that of t'.e An ; the 3 ) at Mar- 

 feillet ; the i lit on tl e Riime ; the lyth 

 atC-enlac ; the 31ft at Auch, where there 

 was a tremendous hinricarc. Du'ing the 

 farr.e two months inc nceivabk inunda- 

 tiois opcuirtd, logether wiih extraordl- 

 raiy (Iv^wer.s of hail, the iV.nes of which 

 vrere as larJr as a man's liiK Tnundei- 

 f nrms hatpcred fo frequently as !"even 

 times in one dav : trees were torn up by 

 the roots, houi'es unroofed, and [.eople 



klilrd. , r /-s 



The Aurora Boreahs of the zid of Oc- 

 tober was the riort rtmarknidc that has 

 been oblcrvcd ii France hnce the vear 

 1769. It was vifi>-le at Lyons, at Gene- 

 ya, and in all the mce rorthcrn pro- 

 vincrs. It furnilfied mean opportunity 

 ol irentioning thecauie, which I havede. 

 jrionftrated in my Aftronomy, namely, 

 elc£l ical emanations; a'^ti of learning 

 that aillines in the Account of hts Voy- 

 aoe f'ys, tlut the Amora Boiealis fome- 

 tirxs cxplo..cs with a great nodej which 

 conliim* the explanation of that pheno- 

 nenon !~y mean'* of eieirhicitv- 



. The earthquake o! the 15th Angiift, 

 "wV.ich (hook, all the buiidings of Alme- 

 ,ia HI Syain, was tdt as far as Holland's 

 sii-d the waters of the Nevis, in the Bour- 

 bonnois, were greatly agitated, and role 



three feet ; which gives me occafion t» 

 call to mind, that at the time of the 

 earthquake of Lifbon, the ift NovenibeT- 

 1755, * confiderable elevatiun was per- 

 ceived in the waters of Bourbon PAr-. 

 chambiult, at the diftance of 187 leagues ; 

 which feems to prove, that the fubtcrra- 

 nean cavities are of vafl: depth, and ex. 

 tend to very great dirtances. 



The poem intitled " Navigation," by 

 Efmenard, which appeared this year, ha« 

 feme connexion with altronomv. Thi« 

 poem, which had long been celebrated, 

 was expefled wih impatience. There- 

 are verJ'es which are very remarkable, ef. 

 pecially thole containing theeulogy of M. 

 Laplace. The author might have men- 

 tioned the immenfe improvement of geo- 

 graphy by means of alUonomical naviga- 

 tion, and of the perpetual aflillance which 

 the Moon affords to miriners. He I'peaks 

 of the alfrolabe, which navigators ntver 

 made ufe of. I am Icrry tooblerve, that, 

 like Rouch(r, in his Poem on the Twelve 

 Monhs, he has doubts concerning the 

 caul't of the fuix and reflux of the (ea.— • 

 Tne.'e blemiflirs will no' be founti in the 

 poem of .M. Gudin, the new edi;ion of 

 which vviii apfear tnisyr-ar. 



I muff likrwife announce a Tnnflation 

 of Ovid's "F.ifti," ty M. Saint- Ange, 

 (ince the months are there defcribed by 

 the rifing of the ftsis. 



It would he an agreeable tafk to write 

 the Hiltory of Adroiioinv, were it not al- 

 w.iys clofcd by the recital of our loffes. 

 One of the moft imrortint is that of M. 

 Mechain, who was not only one of our 

 bei\ aftrjnomers, but one of the moll la- 

 boritus, the moft courageous, and the 

 inoft rrbuft. He fell a viciim to his coui 

 rage, like the youthful Bernicr, vvhofe 

 loli I a few n-ronths ago tleplored. 



Pierre Frai <;ois Andre Mechain wa« 

 born at Laon Auguft 6!h 17+4.. At at> 

 -early age he bad a natural inclination for 

 afbunomy. During the peri.id of his 

 education he wrote to me, offciinghis co- 

 operation in our labours. I fent him the 

 proof (heets of my Affronomy, and he 

 was even then capable of finding faults 

 and of coriecling them. I invited him ti» 

 Palis in 1772- He was employed by M-. 

 Zannni for the Dejot of the Mirine, ard 

 by M. Daiq'.r.er in correfling his Obfer- 

 v-itions. M. Doify, direftor of the De- 

 pot, foon became actjuaiiited with his me- 

 rit, and employed hiii in a moie advan- 

 tageous manner at Verfailles. He theie 

 made obfcrvations j and on the 13th Au- 

 guft 1774 the Academy approved of his 

 firit AisHioir, en cccafion of an edipfe r f 

 Aideb^ran 



