Festa : Hymn Conditor alme siderumTenor
A beautiful label indeed! We could nearly see it swinging in the wind, if Leonardo da Vinci had imagined Java applets.
Notice the laying of the rests at the beginning of the line: if written one above the other, they would have meant a perfect long.
After the first perfection, we notice a sequence made of 4 2 rythms (in minim units), arising from imperfection of each breve by the semibreve on its right side. Such a sequence lasting for a while is, in itself, an indication of perfect time (remark taken from Apel).
This was indeed a tiny example, just for fun...