I’ve read here and there claims that just intonation constantly resets itself, back to an equal tempered baseline. But I don’t think that’s right. As proof, I offer an acappella version of my Alleluia. It modulates quite far, following the circle of fifths; it goes almost two Pythagorean thirds away: Bb to D (up 8 cents) and then D on to B (6 more cents). The seventh in B major, A#, then is 12 cents lower than the B, while the tonic is 14 cents higher than the original reference pitch: presto: an enharmonic A#, +14 cents to B and -12 cents to A#, is very nearly the same as the original Bb reference at 0 cents. The approximately 2 cent difference has a name, too: a schisma.
I recorded the Alleluia, tuning every note, and posted on Fandalism: http://fandalism.com/williamcopper/cJ1g
The score is here: Alleluia
And on my Hartenshield Music website: http://www.hartenshield.com/0580_alleluia.pdf