ce 
Pi egal 
« jllas quam fint in Jove {ciz. 10 horarum aut paulo minus.” 
We dwell with pleafure upon the flighteft conjectures of fuch an 
enlightened mind. 
By the fame formula I computed the time of his rotation, 
taking the denfity of Saturn as deduced by Mr. de la Lande in 
the fourth volume of his Aftronomy, by which it came out 
12 H. 55\4- ; 
I computen it alfo, taking this laft denfity and Mr. Bouguer’s 
ratio of the earth’s diameters (which has many advocates) and on 
this fuppofition it came out 14 H. 44° 4 nearly. 
From the great modern improvement of telefcopes it may 
reafonably be expected that his time of rotation will foon be 
determined by actual obfervation; and from the two fatellites 
lately difcovered by the celebrated Mr. Herfchel, “his denfity 
will foon be more accurately afcertained. 
Anp when the denfity of the Georgian planet fhall have been 
determined by means of his fatellites, difcovered alfo by Mr. 
Herfchel, perhaps fome corre@t law of the denfities may be had ; 
which, if it be found to obtain accurately in thofe planets 
which have fatellites, may, perhaps reafonably, be extended to 
thofe which have none; and enable us to determine the quan- 
tity of matter and denfity of Venus, Mars and Mercury, with- 
out having recourfe to the decrement of the obliquity of the 
ecliptic, a matter fo delicate in itfelf, that even at this day, 
there 
