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VI IT. Ajlronomical Obfervations* In two hellers from M. 

 Francis de Zach, Profeffbr of Mathcmalks^ and Member of 

 the Royal Academies of Sciences at Marfeilles, Dijon, and 

 Lyons, to Mr, Tiberius Cavallo, F. R, S, 



Read December 23, 1784. 



^ 1 R, Lyons, April 4, 1783. 



1SEND you the account of the obfervations on the eclipfc 

 of the moon, which I have made together with the rev* 

 Father le Fevre, Aftronomer at Lyons, in the Obfervatory 

 called au grand College j to which I lliall add the obfervations of 

 the vernal equinox ; fome obfervations on Jupiter's fatellites, 

 made at Marfeilles by M. Saint Jacques de Svlvabelle ; 

 and, laflly, a new folution of a problem that occurs in com- 

 puting the orbits of comets. If you think that thefe obferva- 

 tions do in any way deferve the notice of the Royal Society, ][ 

 fhall be very glad you would communicate them. In order to 

 afcertain the going of the pendulum clock, 1 took feveral cor- 

 refponding altitudes of the fun, which you will find in the fol- 

 lowing table* On the day of the ecliple the Iky was very 

 ferene, nothing could be finer, and it continued fo during the 

 obfervation. I determined to ufe an achromatic telefcope of 

 31 feet length, that fhews objedts in their natural pofition, be- 

 caufe the dihited and uncertain termination of the true fhadow 

 of the earth appears more perfectly defined by fmall than by 

 Vol. LXXV. T large 



