[ log ] 
vations made with the gnomon of St. Sid pice, and 
communicated by Mr. ie Monnier, in the fame vo- 
lume, it fhould feem that that aftronomer is of opi- 
nion, that the obliquity of* the ecliptic hath no other 
variation than what the nutation of the earth’s axis 
will occafiori ; and that therefore we mud either 
abandon the abfolute diminution of the ecliptic, or 
at lead fuppofe it extremely fmal), fince, in the fpace 
of eighteen years, it hath not produced a fenlible. 
alteration. 
° / // 
1738. 3 10 15; 
1740. 3 11 5 
1742. 3 11 48 
1763. 3 4° with the mural quadrant of 5 feet 
318 35 with the large mural inftrument. 
As the refult of the obfervations only, and not the 
obfervations themfelves, are communicated, I have 
only to obferve, that there is a very confiderabje dif- 
ference between the conclufions of the two adrono- 
rners for the fame year 1763, and, at the fame time, 
to declare, my fufpicion, that if the apparent (for fuch 
I apprehend them to be) were reduced to the mean. 
didances, they would probably afford a confirmation 
of the diminution of the ecliptic. For the following 
obfervations of the Sun’s zenith didance, made at 
Shirb'urn-Caftle, near the dimmer foldices. of the 
years 1743, 1746, 1748, and 1766, and of Arftu— 
rus in the years 3743, 1746,. and 1766, when re- 
duced to their mean date at the folftice, do not con- 
firm the aflertion. of Mr. Caffini, but are. an evident r 
and: 
