Warning: this sheet is based on observations of the instruments found, in the absence of testimony from our elders, it remains partly theoretical
Observation of ancient Gascony bagpipes shows that there are generally two types of ligatures to fix the stump of the pihet and that of the wind-holder to the pocket.
This article is more particularly interested in the shape of the notch made on the stumps to receive the ligature in order to fix them on the pocket.
These ligatures participate in the waterproofing of the pocket.
They are of two types, either internal and therefore invisible when the pocket is finished, or external and therefore visible.
Depending on each of these types, the notch on the piece of wood is different. It is in "V" or in "U" with rounded angles for the external ligature and with an edge
at right angles and the other oblique for the internal ligature (diagram n ° 1).
Why several forms of notches on the stumps?
Aside from the aesthetics, which is perhaps an aspect of the matter, it seems that it corresponds more to the major concern of the pipers, to improve the tightness of the bag.
Yes but how?
You can see on diagrams n°2 and n°3 an external ligature. It is easy to understand that if the ligature is not tight enough or there is a fold in the skin, the passage
air between the wood and the skin will be all the easier and the leak inevitable.
In Figures 4 and 5, you will see that the skin is turned inwards. This, coupled with the fact that the inflated bag presses on the vertical edge of the notch,
increases the tightness by creating a double security, the ligature and the pressure of the pocket on the edge of the stump.