The following is an excerpt from Atchley's translation, beginning at the Introit.
Then the pontiff, rising, gives, his right hand to the archdeacon, and his left to the second [deacon] or whoever may be appointed : who, after kissing his hands, walk with him as his supporters. Then the subdeacon-attendant goes before him with the censer, diffusing the perfume of incense : and the seven collets of the district which is responsible for that day, carrying seven lighted candlesticks, go before the pontiff to the altar. But before they arrive at the altar, the deacons put off their planets in the presbytery, and the district-deacon takes them and gives each severally to a collet of the district to which each deacon belongs. Then two collets approach, holding open pixes containing the Holy Element ; and the subdeacon-attendant, taking them, with his hand in the mouth of the pix, shows the Holy Element to the pontiff and the deacon who goes before him. Then the pontiff and the deacon salute the Holy Element with bowed head, and look at the same in order that if there be too many fragments he may cause some of them to be put in the aumbry. After this the pontiff passes on, but before he comes to the choir the bearers of the candlesticks divide, four going to the right and three to the left ; and the pontiff passes between them to the upper part of the choir, and bows his head to the altar. He then rises up, and prays, and makes the sign of the cross on his forehead ; after which he gives the kiss of peace to one of the hebdomadary bishops, and to the archpresbyter, and to all the deacons. Then turning towards the precentor, he signs to him to sing, Glory be to the Father^ and to the Son, etc. ; and the precentor bows to the pontiff, and begins it. Meantime the ruler of the choir precedes the pontiff in order to set his faldstool before the altar, if it should be the season for it : and approaching it, the pontiff prays thereat until the repetition of the verse [i.e. the anthem for the entry]. Now when As it was in the beginning is said, the deacons rise up in order to salute the sides of the altar, first two, and then the rest by twos, and return to the pontiff. And then the latter arises, and kisses the book of the gospels and the altar, and, going to his throne, stands there facing eastwards.
Speaking further of papal liturgy, the following image was sent in by NLM reader "RipK", showing a Mass coram Summo Pontifice in the time of Pope Sixtus IV (d. 1484).
