I seem to remember a rumour that the simple Marian anthem tones, or at the very least the simple Salve Regina, were the work of Henri du Mont

Thank you so much, Patrick!

Now that I know of those websites, I can easily find manuscripts for any other chants of interest. I should have just asked the forum before searching for a few hours on my own.

A slightly unrelated question, but do you know approximately what year the oldest Dominican manuscripts are from, and what form the neumes are? I'm under the impression that Dominican chant went through less change than the other chant traditions. I'd be very interested to see the earliest Dominican manuscripts, if anyone can point me in the right direction.

@a_f_hawkins
Very interesting. With the Salve in particular, I have often wondered about the origin of the simple tone. It seems to me to be extraordinarily well fitted to the words, even better than the solemn tone. It seems to me to be quite an inspired composition, so it is hard for me to imagine it being merely the result of a desire for briefer music.

Is this of interest, https://www.jstor.org/stable/3295122
Jstor has loads of articles, I have access if needed.

In fact, they do not have an unbroken tradition and their way of singing similar to the Vatican edition was influenced by Solesmes and Dom Pothier:

https://www.academia.edu/4898113/_Medieval_and_Modern_Dominican_Chant_in_the_19th_Century_Chant_Old_and_New_ed_William_Renwick_Lions_Bay_Institute_of_Mediaeval_Music_2012_15_47

In the XIII century, the dominican Jerome of Moravia describes ways of ornamentations in chant practice that involves some type of proportionalism and mensuralism.

https://www.academia.edu/853498/Hyeronimus_de_Moravia_Ornamentation_and_Exegesis_in_Gregorian_Old_Roman_and_Byzantine_Chant

In the XIX century a dominican named Bernard made editions of "restored chant" with different lenght values, he made this inspired by the "Tractatus de Musica" of Jerome of Moravia: "After discussing the Gregorian modes, Bernard proceeds to articulate a mensuralist rhythmic system which assigns longer and shorter lengths for individual notes and rests: to give a partial list, a diamond shaped note issung for “one instant” (unam instantiam), a normalsquare note is sung for “one tempus which equals three instants” (unum tempus, seu tresinstantias), and a note with a tail is sung for “one tempus with one instantor sometimes with two instants” (unum tempus habet, cum una aut aliquando cum duabus instantiis). After articulating a six-fold system of lengths, however, Bernard suggests that there can still be some flexibilitywith the rhythym due to the difficulty of exact measurement of musicaltime."