Michael Praetorius (1571 – 1621)
Syntagma Musicum (Vol 2, 1619)
(An online facsimile is available on imslp, here)
The second volume of Praetorius' Syntagma Musicum, De Organographia, deals with the instruments of his time. The quote below comes from Chap. 22, entitled the VIOL[I]N De BRACIO. Famously, he seems to think that we all already know everything about the violin, so he need not write anything further. Interesting, though, his observation about the wire stringing ...
"Viuola, Viola de bracio: that is Violino da brazzo; called a Geige or a fiddle by common folk, and is called "da bracio" because it is held on the arm.
The bass-, tenor- and descant- violin (called Violino or Violetta piccolo, or Rebecchino) are strung with 4 strings; the very smallest (called in French the Pochetto) with three, and they are all tuned in fifths. And because everybody knows about these instruments (apart from the fact that when they are strung with brass and steel strings they produce a softer and sweeter resonance than with other strings), it is unnecessary to point out or write anything more"
Here is Plate 21, depicting (amongst others) the instruments described;
Worth noticing here, is the three different sizes of violin (in addition to the pochette and the octave violin) - and the length of the bows; - all, as far as one can tell, distinctly shorter than the violin itself.