,

I would love to see semiology for the hymns, but I've never come across a resource with the signs for them. A Hymnarius Triplex would be a helpful thing, although most hymns are syllabic anyway. (one note per syllable) so I'm not sure how much different it would be.

The new Solesmes books use different 'square note' neums than the earlier ones, for example, the trigon is written as three small diamonds, and the oriscus is used as the middle note of the salicus, etc. These allow for a 'semiological' interpretation without reprinting the neums from Laon or St Gall, though I've mainly seen them used for the antiphons in the new Antiphonale, not so much the hymns, but I would assume that a speech-rhythm whould also be appropriate.

I don't know how many hymns go that far back in the Gregorian Repertoire to have the staffless neums; they might have been in the common memory of the people like the ordinary settings, which, so I'm told, lack staffless neums. I'm not an expert, but this is what i've gleaned from various sources.

The trick is always getting everyone in the schola to sing the same thing at the same time...

Just a thought here.

I wonder how much you really want to mess with the rhythms of hymns. There is a possibility that what you do will sound interesting and perhaps even "historical." But the point of hymns is not the same as propers. They are really meant to be sung by everyone, even during the office, and the more you mess with the rhythm the more difficult it will be.

From Musicae Sacrae (Pius XII):

The tunes of these hymns, which are often sung in the language of the people, are memorized with almost no effort or labor. The mind grasps the words and the music. They are frequently repeated and completely understood. Hence even boys and girls, learning these sacred hymns at a tender age, are greatly helped by them to know, appreciate and memorize the truths of the faith. Therefore they also serve as a sort of catechism. These religious hymns bring pure and chaste joy to young people and adults during times of recreation. They give a kind of religious grandeur to their more solemn assemblies and gatherings. They bring pious joy, sweet consolation and spiritual progress to Christian families themselves. Hence these popular religious hymns are of great help to the Catholic apostolate and should be carefully cultivated and promoted.

Even though he might have been talking about vernacular hymns, can we argue that something like Veni Creator Spiritus doesn't fit into this category as well?

Hear, hear Gavin!

You can certainly use paleography to interpret hymns. For an example, look at Crux fidelis in the Graduale Triplex. You will, however, run into some problems:

1) While the soloistic, melismatic chants like the Gradual have remarkably little variation from manuscript to manuscript, this hymn doesn't appear to agree with itself from verse to verse.

2) Symbols used for Mass antiphons in 9th and 10th century manuscripts may have entirely different meanings in later manuscripts, and in office antiphons and hymns (cf. Gregorian Chant According to the Manuscipts, Dom Gregory Murray).

3) Hymns are among very few pieces of music that are still widely sung by memory by the people in the pews. I would hesitate to depart from the versions in the official books too much.

Further, this is a very loose definition of semiology, indeed:

I use the word "semiology" loosely. I meant to inquire about a using language oriented principles of full syllabic value only on the final syllable or final notes of compound neumes, with a acceleration on pre-tonic syllables.

While it's true that a general study of the signs supports this as a performance practice, it certainly isn't a rule. There are many instances where two or three notes of neumes are all of full value, not just the final one. In other cases, the final notes are passing tones.

You never need to look at a single manuscript in order to perform a chant musically, and I see no reason why you can give a gentle acceleration at the beginning of a phrase and a little emphasis to syllables with the tonic accent. But if you really want to give a solid semiologically informed performance of hymns, you will have to do some trail blazing on your own. Most chant scholars have devoted their attention to the proper antiphons of the Mass.