I8d Trench National Institute. 



in order that the necessary precautions may be taken. It 

 is on this account that for some time the Connohsauce dts 

 Terns has announced for all the new and fiill moons the 

 force of the tides, abstracting from every local and acci- 

 dental circumstance. The tides of \^eiitoPe and Germinal 

 last were announced as about to he the highest in the 

 course of the year. Tliey attracted the attention of ob- 

 servers and of the curious. If the expectation of the latter 

 was not fully answered, the former had reason to be more 

 satisfied. These tides, indeed, were the highest of any re- 

 membered : but the atmosphere was calm ; and consequently 

 none of tliose accidents, the possibility of which only was 

 foreseen, could take place. C. Rochon communicated to 

 the class what he observed at Brest, and C. Scptfontaines 

 has transmitted to us A^hat lie saw at Calais. Their notices 

 induced C. Laplace to read a memoir ; at the conclusion of 

 which the class, sensible of the necessity of a scries of ob- 

 servations made at different ports, and according to an 

 uniform method, appointed a commission charged with 

 drawing up instructions proper for serving as a guide to 

 observers. 



The report of the commission has been printed, to be 

 distributed in the ports. The ministers have promised to 

 give their orders; and the series of observations destined to 

 make known what part of the pha?nomena of the tides de- 

 pends on periodical and genera! causes, and what depends 

 on local or accidental causes, will soon be begun. 



The new planets discovered by Piazzi and Olbers conti- 

 nue to engage the attention of astronomers. Notwith^ 

 standing the smallness of the arc which they have passed 

 through in our sight, and notwithstanding the consider- 

 able perturbations which they experience fvom .Tupiter, we 

 have already obtained the elements of their orbits with suf- 

 ficient procis'ro.i to find again these bodies in the place in- 

 dicated bv calculation, when they become visible, after hav- 

 ing: been several months lost in the rays of the sun. The 

 greatest difficulty arises from their extreme smallness, 

 which sometimes causes us to doubt wlvctherwe have thent 

 in the field of the telescope. Tliis is true in regard to 

 Pallas in particular, which appears sometimes like a star of 

 the 10th and nth, or even the i2th magnitude, while- 

 Ceres appears of the 7th or 8th. But as there is some- 

 thing too. arbitrary in this distribution of the stars accord- 

 ing to the order of their magnitudes, it will be better to 

 say with Messier, that Pallas is the smallest object that can 

 be distiilgui&hcd with an excellent telescope. 



