The poetic word glamour is the same as grammar, which had in the Middle Ages the sense of mysterious learning. From the same source we have the French corruption grimoire, "a booke of conjuring" (Cotgrave). Glamour and gramarye were both revived by Scott—
"A moment then the volume spread,
And one short spell therein he read;
It had much of glamour might."
(Lay of the Last Minstrel, iii. 9.)
"And how he sought her castle high,
That morn, by help of gramarye."
(Ibid., v. 27.)
For the change of r to l we have the parallel of flounce for older frounce (p. [60]). Quire is the same word as quair, in the "King's Quair" i.e. book. Its Mid. English form is quayer, Old Fr. quaer, caer (cahier), Vulgar Lat. *quaternum, for quaternio, "a quier with foure sheetes" (Cooper).
EASTERN DOUBLETS
Oriental words have sometimes come into the language by very diverse routes. Sirup, or syrup, sherbet, and (rum)-shrub are of identical origin, ultimately Arabic. Sirup, which comes through Spanish and French, was once used, like treacle (p. [75]), of medicinal compounds—
"Not poppy, nor mandragora,
Nor all the drowsy syrups of the world,
Shall ever medicine thee to that sweet sleep
Which thou ow'dst yesterday."
(Othello, iii. 3.)