42 
Pliny's i?"atueal histobt. 
[Book 11. 
him at their morniiig setting, they become invisible and pass 
beyond him. They then rise in the evening, at the distances 
which v^^ere mentioned above. After this they return back 
to the sun and are concealed in their evening setting. The 
star Venus becomes stationary when at its two points of 
greatest elongation, that of the morning and of the evening, 
according to their respective risings. The stationary points 
of Mercury are so very brief, that they cannot be correctly 
observed. 
CHAP. 13. — WHY THE SAME STABS APPEAR AT SOME TIMES 
■« 
MORE LOFTY AND AT OTHER TIMES MORE NEAR. 
The above is an account of the aspects and the occultations 
of the planets, a subject which is rendered very complicated 
by their motions, and is involved in much that is wonderful ; 
especially, when we observe that they change their size and 
colour, and that the same stars at one time approach the 
north, and then go to the south, and are now seen near the 
earth, and then suddenly approach the heavens. If on this 
subject I deliver opinions different from my predecessors, I 
acknowledge that I am indebted for them to those indivi- 
duals who first pointed out to us the proper mode of inquiry; 
let no one then ever despair of benefiting future ages. 
But these things depend upon many difierent causes. The 
first cause is the nature of the circles described by the stars, 
which the Grreeks term a^sides^, for we are obliged to use 
Greek terms. JSTow each of the planets has its own circle, 
and this a difierent one from that of the world^ ; because the 
earth is placed in the centre of the heavens, with respect to 
the two extremities, which are called the poles, and also in 
from the sun at wliich Venus and Mercury become stationary, and when 
they attain their greatest elongations ; Ajasson, ii. 328, 329. According 
to Ptolemv, Magn. Constr. hb. viii. cap. V, the evening setting of Yenus 
is at 5° 40' from the sun, and that of Mercury at 11° 30'. 
^ " * A(//(§, hgneus rotse circulus, ab citttu) necto;" Hederic in loco. The 
term is employed in a somewhat different sense by the modem astrono- 
mers, to signify the point in the orbit of a planet, when it is either at the 
greatest or the least distance from the earth, or the body about which it 
revolves ; the former being termed the apogee, aphehon, or the higher 
apsis ; the latter the perigee, perhehon, or lower apsis ; Jennings on the 
Globes, pp. 64, 65. 
^ "mundo." 
