M, DE Zach*s AJlronomkd Ohjervatlons^ 



143 



Father le FeVre's obfervations with a refle£lor 55 inches 

 focal length, magnifying 300 tinaes. 



IMMERSIONS. 



Grimaldi touches the Ihadow 

 Kepler touches the fliadow 

 all in the fliadow 



Copernicus touches the fiiadow 

 all in the fliadow 



Mare Serenitatis touches the fliadow 



■ all in the fhadow 



Mare Crifium touches the fliadow 



all in the ftiadow 



Total immerfion 



E M E R S I O N S. 

 Beginning of the emerfion 

 Grimaldi emerged 

 Kepler all out of the fliadow 

 Copernicus all out 

 Mare Serenitatis all out 

 Crifium all out - - 



End of the eclipfe 

 Total duration 



Time by the 

 clock. 



h. 



7 

 7 



41 43 

 52 2 



7 53 24 



8 o 22 

 8 2 26 

 8 16 7 

 8 26 2 

 8 z-?, 28 



8 38 54 



10 19 42 



10 23 24 



10 35 43 



10 43 4 



\o 57 19 



11 ^5 50 

 II 20 22 



Apparent 



time. 



h. 



7 

 8 



8 



8 



3 



8 



8 



8 



8 



8 



3 



5 



12 



H 

 28 



37 



45 

 48 



50 



// 



Zl 



SI 



19 



17 



21 



3 

 58 



25 

 SZ 

 52 



10 31 



47 

 10 35 29 



10 47 49 



io 55 10 



11 9 26 

 II 27 57 

 II 32 30 



3 39 20 



The obfervation of the vernal equinox was made at tlie 

 gnomon. The height of thi« gnomon, taken from the center 

 of the hole by which the beams of the fun come in, is 1878 

 lines of a French inch ; the diftance from the bottom of the 

 gnomon to the equino£lial point is 1928 ; the dlftance from the 

 upper limb of the lun's image to the equlnodlial pol.'jt was 

 found 16,7 ; the diftance from the under Jimb 23,4 ; the dia- 

 meter of the hole = 6 ; therefore the diftance from the bottom 

 to the upper limb 1928-16,74-3=191 4,3 , to the under limb 

 1928 + 23,4 — 3=1948,4; which gives the time the equi^- 

 nox happened, the 20th of March, 5 h. 56' ^2!' P.M. 



4 Obfervations 



