the month and hour of the day by making calculations from the observed position of the sun in the sky, and from the length of shadows, although, says Chaucer, “he were not depe expert in lore.”[51] Such references to technical details of astronomy as we find in this passage are, however, not common in Chaucer’s poetry; in his Treatise on the Astrolabe, on the other hand, a professedly scientific work designed to instruct his young son Louis in those elements of astronomy and astrology that were necessary for learning the use of the astrolabe, we have sufficient evidence that he was thoroughly familiar with the technical details of the astronomical science of his day.

In Chaucer’s poetry the astronomical references employed are almost wholly of two kinds: references showing the time of day or season of the year at which the events narrated are supposed to take place; and figurative allusions for purposes of illustration or comparison. Figurative uses of astronomy in Chaucer vary from simple similes as in the Prologue to the Canterbury Tales, where the friar’s eyes are compared to twinkling stars[52] to extended allegories like the Compleynt of Mars in which the myth of Venus and Mars is related by describing the motions of the planets Venus and Mars for a certain period during which Venus overtakes Mars, they are in conjunction[53] for a short time, and then Venus because of her greater apparent velocity leaves Mars behind. One of the most magnificent astronomical figures employed by Chaucer is in the Hous of Fame. Chaucer looks up into the heavens and sees a great golden eagle near the sun, a sight so splendid that men could never have beheld its equal ‘unless the heaven had won another sun:’

“Hit was of golde, and shone so bright,
That never saw men such a sighte,
But-if the heven hadde y-wonne
Al newe of golde another sonne;
So shoon the egles fethres brighte,
And somwhat dounward gan hit lighte.”[54]

Besides mentioning the heavenly bodies in time references and figurative allusions, Chaucer also employs them often in descriptions of day and night, of dawn and twilight, and of the seasons. It is with a poet’s joy in the warm spring sun that he writes:

“Bright was the day, and blew the firmament,
Phebus of gold his stremes doun hath sent,
To gladen every flour with his warmnesse.”[55]

and with a poet’s delight in the new life and vigor that nature puts forth when spring comes that he writes the lines:

“Forgeten had the erthe his pore estat
Of winter, that him naked made and mat,
And with his swerd of cold so sore greved;
Now hath the atempre sonne al that releved
That naked was, and clad hit new agayn.”[56]

Chaucer’s astronomical allusions, then, except in the Treatise on the Astrolabe and in his translation of Boethius de Consolatione Philosophiae, in which a philosophical interest in celestial phenomena is displayed, are almost invariably employed with poetic purpose. These poetical allusions to heavenly phenomena, however, together with the more technical and detailed references in Chaucer’s prose works give evidence of a rather extensive knowledge of astronomy. With all of the important observed movements of the heavenly bodies he was perfectly familiar and it is rather remarkable how many of these he uses in his poetry without giving one the feeling that he is airing his knowledge.

1. The Sun

Of all the heavenly bodies the one most often mentioned and employed for poetic purposes by Chaucer is the sun. Chaucer has many epithets for the sun, but speaks of him perhaps most often in the classical manner as Phebus or Apollo. He is called the “golden tressed Phebus”[57] or the “laurer-crowned Phebus;”[58] and when he makes Mars flee from Venus’ palace he is called the “candel of Ielosye.”[59] In the following passage Chaucer uses three different epithets for the sun within two lines:

“The dayes honour, and the hevenes ye,
The nightes fo, al this clepe I the sonne,
Gan westren faste, and dounward for to wrye,
As he that hadde his dayes cours y-ronne;”[60]

Sometimes Chaucer gives the sun the various accessories with which classical myth had endowed him—the four swift steeds, the rosy chariot and fiery torches:

“And Phebus with his rosy carte sone
Gan after that to dresse him up to fare.”[61]

“‘now am I war
That Pirous and tho swifte stedes three,
Which that drawen forth the sonnes char,
Hath goon some by-path in despyt of me;’”[62]

“Phebus, that was comen hastely
Within the paleys-yates sturdely,
With torche in honde, of which the stremes brighte
On Venus chambre knokkeden ful lighte.”[63]

Almost always when Chaucer wishes to mention the time of day at which the events he is relating take place, he does so by describing the sun’s position in the sky or the direction of his motion. We can imagine that Chaucer often smiled as he did this, for he sometimes humorously apologizes for his poetical conceits and conventions by expressing his idea immediately afterwards in perfectly plain terms. Such is the case in the passage already quoted where Chaucer refers to the sun by the epithets “dayes honour,” “hevenes ye,” and “nightes fo” and then explains them by saying “al this clepe I the sonne;” and in the lines:

“Til