The following list is from van Acht [1], with additional data from Langwill [2] and Bouterse [3[ Dutch makers with numbers of extant traverso´s and dates.
| name | number of extant traverso´s | |
| Abraham v Aardenberg | 1672-1717(?) |
1 |
| Jan Barend Beuker | 1691-1750 |
9 |
| Willem Beukers Sr. Willem Beukers Jr. |
1666-1750(?) 1703-1781 |
3 |
| Philip Borkens | 1693-1765 |
2 |
| Johannes Christiani | 1786-1858 |
2 |
| Michel Duval | 1747-1815 |
2 |
| Frank Eerens | 1694-1750 |
4 |
| D.v Gulik | 1 |
|
| Richard Haka | 1646-1705 |
1 |
| Claas v Hallum | 1720-1791 |
1 |
| Albertus&Jan v Heerde | 1674-1720 1704-1750 |
3 |
| Barend Hemsing | 1703(4)-1776 |
2.5 |
| Engelbert Terton | 1710-1752 |
1 |
| Weijdemuller | 3 |
|
| Robbert Wijne | 1698-1774 |
8 some as fragments |
| Willem WIjne | 1730-1816 |
1 |
We may reason from this about the number of traverso´s produced in the Netherlands from 1660 to 1800.
We see 18 makers here. We will have missed one or two, so let us say there were 20 for ease of calculating. Stradivarius took two weeks for a violin, so let us say they took one week for a traverso. However they made different woodwind instruments. In the beginning more, because they made recorders, in the end most of the traverso makers probably made only traverso`s. So let us say they made one per month. On average they produced some 40 years. So 40*12*20=9600 traverso. Let us say 10,000. We still Have 44.5, let us say 50 traverso´s. Therefore we have something like 50/10,000=0.5% instruments left. This is a very rough reasoning but it gives us an order of magnitude, it may be 1% or it maybe .25%, but somewhere there it must be. Probably the 0.5% is reasonable.
This shows how scarce the evidence is that we have at our disposal. If we assume that half of the instruments they made were top quality (that is much of course) we have only .25% top quality evidence. If on top of this we realize that they had no electronic tuners, so did all the tuning by ear there is a good reason to say that we have very little left.
The situation is different for violins for several reasons. The instrument has not changed as the flute did from one keyed conical to Boehm. On the contrary, the best instruments, albeit with adaptations, are still valued higher than present day instruments! So a much higher percentage of especially the good instruments is left. This simply implies that only faithful copying may not be wise at all. I think that we have to reconstruct as well as copy. We have to use our own intelligence. Isn't that nice!
[1] R v Acht Dutch wind instruments from the baroque period. Scientific qualities and features. Musique.Images.Instruments No 4.
[2]The New Langwill Index. Tony Bingham London, ISBN 0-946113-04-1
[3] Dutch woodwind instruments and their makers, 1660-1760, Ph. D. Thesis of M. C. J. Bouterse, available on CDROM from the author or from the Dutch "vereniging voor huismuziek" info@huismuziek.nl

