"'I saugh thyn hornes olde eek by the morwe,'"[100]
is practically the only one in which Chaucer gives any hint of the times
at which the moon in her various phases may be seen. The phase of the 'new
moon,' when the moon is in conjunction with the sun (i. e., between the
earth and the sun, so that we cannot see the illuminated hemisphere of the
moon) is mentioned in the same poem:
"Right sone upon the chaunging of the mone,
Whan lightles is the world a night or tweyne."[101]
There is a very definite description of three of the moon's phases in the
following passage from _Boethius_:[102] "so that the mone som-tyme shyning
with hir ful hornes, meting with alle the bemes of the sonne hir brother,
hydeth the sterres that ben lesse; and som-tyme, whan the mone, pale with
hir derke hornes, approcheth the sonne, leseth hir lightes;" The moon
'shining with her full horns' means with her horns filled up as at full
moon when she is in a position opposite both earth and sun so that she
reflects upon the earth all the rays of the sun. The moon "with derke
hornes" refers of course to the waning moon, a thin crescent near the sun
and almost obscured in his light, which approaching nearer the sun is
entirely lost to our view in his rays and becomes the new moon.
Chaucer's most interesting references to the moon are found in the prayer
of Aurelius to the sun in the _Frankeleyns Tale_. Dorigen has jestingly
promised to have pity on Aurelius as soon as he shall remove all the rocks
from along the coast of Brittany, and Aurelius prays to the sun, or
Apollo, to help him by enlisting the aid of the moon, in accomplishing
this feat. The sun's sister, Lucina, or the moon, is chief goddess of the
sea; just as she desires to follow the sun and be quickened and
illuminated by him, so the sea desires to follow her:
"'Your blisful suster, Lucina the shene,
That of the see is chief goddesse and quene,
Though Neptunus have deitee in the see,
Yet emperesse aboven him is she:
Ye knowen wel, lord, that right as hir desyr
Is to be quiked and lightned of your fyr,
For which she folweth yow ful bisily,
Right so the see desyreth naturelly
To folwen hir, as she that is goddesse
Bothe in the see and riveres more and lesse.'"[103]
In calling Lucina chief goddess of the sea and speaking of the sea's
desire to follow her, Chaucer is, of course alluding to the moon's effect
upon the tides; and in the line:
"'Is to be quiked and lightned of your fyr,'"
the reference is to the fact that the moon derives her light from the sun.
Instead of leaving it to the sun-god to find a way of removing the rocks
for him, Aurelius proceeds to give explicit instructions as to how this
may be accomplished. As the highest tides occur when the moon is in
opposition or in conjunction with the sun, if the moon could only be kept
in either of these positions with regard to the sun for a long enough
time, so great a flood would be produced, Aurelius thinks, that the rocks
would be washed away. So he prays Phebus to induce the moon to slacken her
speed at her next opposition in Leo and for two years to traverse her
sphere with the same (apparent) velocity as that of the sun, thus
remaining in opposition with him:
"'Wherfore, lord Phebus, this is my requeste--
Do this miracle, or do myn herte breste--
That now, next at this opposicioun,
Which in the signe shal be of the Leoun,
As preyeth hir so greet a flood to bringe,
That fyve fadme at the leeste it overspringe
The hyeste rokke in Armorik Briteyne;
And lat this flood endure yeres tweyne;
. . . . . . . . .
Preye hir she go no faster cours than ye,
I seye, preyeth your suster that she go
No faster cours than ye thise yeres two.
Than shal she been evene atte fulle alway,
And spring-flood laste bothe night and day.'"[104]
References to eclipses of the moon occur seldom in Chaucer. In the second
part of the _Romaunt of the Rose_, which is included in complete editions
of Chaucer's works but which he almost certainly did not write, there is a
description of a lunar eclipse and of its causes. Fickleness in love is
compared to an eclipse:
"For it shal chaungen wonder sone,
And take eclips right as the mone,
Whan she is from us (y)-let
Thurgh erthe, that bitwixe is set
The sonne and hir, as it may falle,
Be it in party, or in alle;
The shadowe maketh her bemis merke,
And hir hornes to shewe derke,
That part where she hath lost hir lyght
Of Phebus fully, and the sight;
Til, whan the shadowe is overpast,
She is enlumined ageyn as faste,
Thurgh brightnesse of the sonne bemes
That yeveth to hir ageyn hir lemes."[105]
This passage is so clear that it needs no explanation.
An eclipse of the moon, since it is caused by the passing of the moon into
the shadow of the earth, can only take place when the moon is full, that
is, in _opposition_ to the sun. This fact is suggested in a reference in
_Boethius_ to a lunar eclipse:
"the hornes of the fulle mone wexen pale and infect by the boundes of
the derke night;"[106]
In the next lines Chaucer mentions the fact that the stars which are lost
to sight in the bright rays of the full moon become visible during an
eclipse:
"and ... the mone, derk and confuse, discovereth the sterres that she
hadde y-covered by hir clere visage."[107]