Tr. On the summit of the hill you placed firm the wheel of the chariot; the other wheel goes around the heaven.
O Ashvins, aghnyasya of the hill; mūrdhani on the summit; rathasya of the chariot; cakram one wheel; niyemathuḥ you placed firm; anyat the other wheel; dyām the heaven; pari around; īyate goes.
aghnyaḥ : cow, say some; Prajapati Aditya, says Skandasvamin; not to be stuck, hill, because of firmness, says Sayana. Here it should be taken as hill, because so it coheres in purport. One wheel of the chariot of the Ashvins is in a high place on earth, the other in heavens. The Chariot itself, it is to be noted, is a symbolic word denoting special, regulated movement. Of this one wheel is kept on the summit of the hill, the other goes round the heavens or towards the heavens. (pari denotes action, should be taken as prati 'towards' says Skandasvamin.)
This is the secret import to be noted. One wheel of the Ashvins is placed on the summit of the plane of physical consciousness, the peak of the ripened consciousness of man; on the peak of such a hill, verily, is first welcomed the ray of the dawn of knowledge. There does Goddess Usha, daughter of Heaven, bride of the honeyed Ashvins, ride the luminous chariot of the Ashvins and ascend the heaven, where the other wheel of the chariot goes to the divine station. What has been said elesewhere regarding the activity of the Ashvins must be kept in mind (1.3.3.) The movement of the Ashvins in the heaven and on earth, ‘on the summit of the hill'; this becomes clear in another Rik : 'which stations the Ashvins hold in the streams of heaven, in the herbs and in men; they rest on the summits of the hill’ (7.70.3). The chariot of the Ashvins is luminous, ‘come Ashvins in the car of the solar skin’ (8.8.2); 'gold-seated, gold-reined, touching the heaven' (luminous cover) (8.5.28); note that gold, sun, light denote relation with the Truth. “Your chariot born of truth, urged from the hill (3.58.8) There is also mention in plural of Usha along with the Ashvins riding the chariot : 'Blessed those ancient Dawns, luminous with plenty, true born of truth (4.51.7.)
Now three Riks to Usha. Of these this is the first, twentieth in the hymn.