The GEORGIUM SIDUS. 313 



THE manner of obfervation, and the inftrument which I make 

 ufe of, appear to me to have feveral advantages which are not un- 

 worthy of the attention of Aftronomers. An account of them 

 will therefore be communicated on fome future occafion. 



FROM thefe places, it is eafy to determine the inclination of 

 the Planet's orbit to the plane of the Ecliptic, and the place of 

 its Node, which are as follow : 



j. o " ' 

 Long. Node, Jan. i. 1786. 2.12.48.45 



Inclin. Orbit, 46. 26 



I WAS now enabled to reduce thefe Ecliptic places to the or- 

 bit itfelf, and thus to determine the arches of this orbit de- 

 fcribed during the intervals between the oppofitions. 



I THEN took the oppofition which was obferved on the 31(1 

 of December 1783 for an epoch, to which all the obfervations 

 mould be reduced. The interval of time between this and the 

 preceding oppofition was 369^. 15 b. 49'. 28". I counted 

 back another equal interval, which brought me within a few 

 minutes of the time of oppofition 1781, and I computed (by 

 means of the heliocentric motion, already determined for that 

 oppofition with fufficient accuracy) the place of the Planet for 

 the beginning of the above mentioned interval. In like man- 

 ner, I computed its place for two equal intervals of 369 d. i$h. 

 49' 28", reckoned forward from the epoch. Thus I obtained 

 four angles in the orbit, defcribed in equal intervals of time. 

 The differences of thefe angles mowed the inequality of the 

 Planet's angular motion. From this inequality alone, we are 

 to determine the chief elements of its excentric orbit. 



I IMMEDIATELY found, that thefe differences, ftrictly taken, 

 had irregularities which are inconfiftent with the moft remark- 

 able circumftances of the Planet's motions. It appeared, there- 

 fore, that the obfervations muft be corrected, as far as is con- 

 fiftent with the probability of their inaccuracy. With refped 



R r to 



