Giap. 16.] 
ACCor]srT OP the -world. 
49 
well as the laws to wliieli tliey are subject, wbich migbt be 
mentioned. Eor example, the planet Mars, wbose course is 
tbe most difficult to observe \ nwer becomes stationary wben 
Jupiter is in tbe trine aspect, very rarely wben he is 60 degrees 
from the sun, which number is one-sixth of the circuit of the 
heavens^ ; nor does he ever rise in the same sign with Jupiter, 
except in Cancer and Leo. The star Mercury seldom has 
his evening risings in Pisces, but very frequently in Virgo, 
and his morning risings in Libra ; he has also his morning 
rising in Aquarius, very rarely in Leo. He never becomes 
retrograde either in Taurus or in G-emini, nor until the 25th 
degree of Cancer. The Moon makes her double conjunction 
with the sun in no other sign except G-emini, while Sagit- 
tarius is the only sign in which she has sometimes no con- 
junction at all. The old and the new moon are visible on 
the same day or night in no other sign except Aries, and 
indeed it has happened very seldom to any one to have -wit- 
nessed it. From this circumstance it was that the tale of 
Lynceus's quick-sightedness originated^, Saturn and Mars 
are invisible at most for 170 days ; Jupiter for 36, or, at the 
least, for 10 days less than this ; Venus for 69, or, at the least, 
for 52 ; Mercury for 13, or, at the most, for 18^. 
CHAP. 16. (18.) — THE REASOI?" WHY THE STARS ARE OP DIF- 
I^ERENT COLOURS. 
The difference of their colour depends on the difference in 
their altitudes ; for they acquire a resemblance to those planets 
into the vapour of which they are carried, the orbit of each 
tinging those that approach it in each direction. A colder 
planet renders one that approaches it paler, one more hot 
^ " . . . . quae (steUa Martis) Tit maxime excentrica volvitur, motus 
etiam maxime dissonos habere diu visa est . . . . ;" Alexandre inLemaire, 
ii. 180. 
2 " . . . . qui ntmierus sexangnlas mundi efficit formas." 
Lynceus was one of the Argonauts and was celebrated for the acnte- 
ness of his vision ; Yal. Flaccus, i. 462 et seq. 
^ The relative situation of these astronomical phsenomena has changed 
since the time of PHny, in consequence of the precession of the equinoxes. 
For an illustration and explanation of the various statements in this 
chapter I may refer to the remarks of Marcus in Ajasson, ii. 368-370* 
VOL. I. E 
