Hi Richard, things are a bit different. The breacking index is the theoric point were a gut string broken, in my = case an average of 260 Hzxmt. so it mean that in a lute in g with a-440 Hz the vibrating string lenght = were a gut string (of every gauge) is 66 cms. For a working lenght need a short vibrating string length than 66 cm: = there are several works (see Segerman etc) that shows that lutes worked = at 2-3 semitones down the limit. I.e. in our case 59-60 cms is a suitable vibrating string length. When you put the top string 'in g' it work anyway to the breackage. In = other worlds at 2-3 semitones close to the breackage a gut string start = to became without any displacement, i.e. elongation under increasing of = tension. Baron (1727) wrote that there are examples were a Roman lute top string = lasted 4 weeks. This was consider quite fantastic by him. I am not optimistic, like stringkmaker I normally obtain, from guts of = .40 mm gauge breacking index of 320 HzXmt, and this with lamb gut with = not modern chemical treatments.
Mimmo --
