Treatise on the Mass (from the Stowe Missal), Part 01

According to Wikipedia:

The Stowe Missal is a missal written in Latin and Gaelic which was transcribed at Lorrha Monastery in the ninth century. Also known as the Lorrha Missal, it is known as the 'Stowe' Missal due to its acquisition by one of the Dukes of Buckingham for the Stowe manuscripts collection. Stowe House was sold in 1849 to the Earl of Ashburnham. In 1883 the missal was purchased by the British Government and deposited in the Royal Irish Academy.

The form of the liturgy and the services of baptism and unction reflect a Celtic usage dating from before 650 AD. Whether this is the usage brought by St. Patrick in the early fifth century, or a later revision is not certain. Used during an era in which Christianity was neither universal nor fully understood, it asserts in detail the redemptive nature of Jesus Christ's birth, death and resurrection. The writer(s) assumes that those participating in the Eucharist must have every detail repeated clearly.

Here we are going to look upon a tract on the Mass (folios 65-67) written in Old Irish. I would first provide the original Gaelic and Latin text (as it appears in the Missal), a more 'tidied up' version (with proper spacings and punctuations), and an English translation.

A TREATISE ON THE MASS
from the Stowe Missal

INdaltoir fiugor dīgrīme īmab · in cailech isfig īnaecl fuirmed & rofothiged forīgrimī & fōmartri īnafathe & aliorū · huisq: p: ī calicem & iss canar occo· peto te pat depcor té filii· obsecro te sps scae·i·fig īphop toresset in aecla · Oblae iar– suƥ altare·i·īƭƭ iss canar occo·i·ihs xps Α & ω ḣ÷ ṕncipiu & finis · fig cuirp cr rosuidiged hi linannart brond maire · Fin iar– aṙhuisq2 hicaelecḥ·i·deacht cr aradonacht & arīpōp īaīsir thuisten iss canar ocsuidiu · Remit& pr īdulget fl2· misseret sps scs :·

Ind altoir, fiugor ind ingrimme immabred.
In cailech, is figor inna eclaise foruirmed ocus rofothaiged for ingrimmim ocus for martri inna fathe et aliorum.
Huisque (/ Huisce) prius in calicem, ocus issed canar occo: Peto te Pater; deprecor te, Filii (/ Filii); obsecro te, Spiritus Sanctae (/ Sancte); idon, figor in phopuil toresset in aeclesia (/ ecclesia).
Oblae iarum super altare, id est, intrat. Issed canar occo, idon, Iesus Christus, a et ω, hoc est, principium et finis. Figor cuirp Crist, rosuidiged hi linannart brond Maire.
Fin iarum ar huisce hi caelech, idon, deacht Crist ar a donacht (/ doenacht), ocus ar in popul, in aimsir thuisten. Issed canar oc suidiu: Remitet (/ Remittat) Pater, indulget (/ indulgeat) Filius, miseretur (/ misereatur) Spiritus Sanctus.

The altar, a figure of the persecution which is inflicted.
The chalice, it is a figure of the Church which was set and founded upon the persecution and upon the martyrdom of the prophets et aliorum (and of others).
Water, first, in calicem, (into the chalice) and what is chanted by them is: Peto te Pater; deprecor te Fili; obsecro te, Spiritus Sancte ("I pray to you, O Father; I ask intercession of you, O Son; I appeal to you, O Holy Spirit"), that is, a figure of the people that was poured in Ecclesia (into the Church).
The Host, then, super altare, id est, intrat (over the altar, that is, it enters). What is chanted by them is: Iesus Christus, Αlpha et Omega, hoc est, principium et finis ("Jesus Christ, Alpha and Omega, this is the beginning and the end"). A figure of the body of Christ which was placed in the linen-sheet of the womb of Mary.
Wine afterwards upon water in the chalice, that is, the divinity of Christ upon His humanity and upon the people, at the time of Incarnation. It is what is chanted thereat: Remittat Pater, indulgeat Filius, miseretur Spiritus Sanctus ("May the Father remit, may the Son pardon, may the Holy Spirit have mercy").

Acanar dind off fsen it ītroit & orthana & tormach corrigi liacht naps & ψalm ṅ dig isfigor recto aicnith īsin inroaithnuiged [aithgne] cr triahuili baullo & gnímo · Liacht aps im & salṁ digd & hoṡuidiu codinochtad is foraithmet· rechta litre īrofiugd cr [acht] nadfess cadacht cidrofiugd and · Indinochtad corricileth īna oblae & īcailich & acanar occo it sos & aillóir corrici oblata isforet rechta fáthe hitarc[h]et cr cofoll: acht nath naiccess corogenir :~

A canar dind offriund forsen, iter Introit ocus Orthana ocus Tormach, corrigi Liacht nApstal ocus ψalm (/ Salm) ṅdigrad, is figor recto aicnith insin, in roaithnuiged [aithgne] Crist tria huili baullo ocus gnimo.
Liacht nApstol, immorro, ocus Salm digrad ocus ho shuidiu co Dinochtad, is foraithmet rechta litre, in rofiugrad Crist, [acht] nadfess cadacht, cid rofiugrad and.
In dinochtad corrici leth inna oblae ocus in cailich ocus a canar occo, itir Soscel ocus Ailloir, corrici Oblata, is foraithmet rechta fathe, hi tarc(h)et Crist co follus, acht nathnaiccess co rogenir.

What is chanted of the Mass thereafter - both Introit and Prayers and Addition - up to the Lesson of Apostles (the Epistle) and the bigradual Psalm, it is a figure of the law of nature, wherein was renewed [the knowledge of] Christ through all His members and deeds.
The Lesson of Apostles, moreover, and the bigradual Psalm and from that to the Uncovering (of the chalice), it is a memorial of the law of the Letter wherein was figured Christ, who was not known as yet, though He was figured therein.
The elevation of the chalice, after the full uncovering thereof, quando canitur oblata (when the Oblata is chanted), that is a commemoration of Christ's birth and of His glory through signs and miracles.
The Uncovering, as far as half, of the oblation and of the chalice, and what is chanted by them - both Gospel and Benediction, as far as Oblata, it is a memorial of the law of the Prophets, wherein Christ was foretold clearly, but was not seen until He was born.