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From: Renee Mattie (no email)
Date: Fri Dec 02 2005 - 19:11:19 EST
Here is an example of a traverse board that looks like Duane Cline's
drawing:
http://www.mariner.org/educationalad/ageofex/images/traverse.jpg
on http://www.mariner.org/educationalad/ageofex/navmethods.php
You can see that the keeper pin for the speed pegs is in the middle of the
speed peg holes.
Here is an example of a traverse board that might be used according to the
description given by Duane Cline on the same web page:
http://home.comcast.net/~saville/traverse_board.htm
http://home.comcast.net/~saville/tboard1640.jpg
The first image is of a "replica of an Italian Traverse Board made in the
1640's". It shows 8 rows of 10 peg-holes. Four rows are on the left, four
on the right. There are no "peg keepers" (though there is an empty hole
that might do for a "peg belaying pin" in the center of the compass rose),
and the pegs seem to be inserted randomly.
On the same page, the second image is of a traverse board with an awful lot
of speed-peg holes. The traverse board was "made for the Salem "Friendship":
a replica of a 1797 merchant vessel out of Salem, Massachusetts"
http://home.comcast.net/~saville/Straverse.jpg
There are two columns of speed holes.
Each column has 8 rows of 10 peg-holes -- 9 in a staggered line, plus one
more (home?) peg-hole set apart from the others.
The explanation of these holes from the proprietor of Backstaff Instruments
(Gregg Germain?) is:
"Each 4 hour watch was broken up into 8, 30 minute segments. At the start of
a new watch, the log was hove. The measured speed was indicated in knots and
eigths of a knot by placing pegs in the first two rows of holes at the
bottom of the traverse board. The first row denoted knots; the second eigths
of a knot. There are eight sets of two rows of holes at the bottom of the
Traverse Board: one set per 30 minute "glass" of the watch."
He does not indicate what he used for a model, or where he got the
information on how it was used. It would seem that the right-hand column
has more than enough holes for recording eighths. Speeds up to 9 + 9/8 (10
1/8) knots could have been recorded. But that sounds like a confusing way
to do it. A traverse board was supposed to reduce navigational errors by
making it easy to record sailings every glass. Would eighths of a knot
really have been recorded in the 1790s?
Again, there is a hole for a "peg belaying pin" in the center of the compass
rose, but no pin, no strings, and no pegs.
Renee Mattie
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