Patrick Smith
wrote
>
>You might have a look at Jean Harrington's work on the relationship between
>pipestem diameter and age.  There is a brief summary in Jim Deetz's book "In
>Small Things Forgotten"
>
>        Time periods and average bore diameters as follows:
>
 Also have a look at British Archaeological Reports  Supplementry series 36
(1977) for the excavation report of the Vergulde Draeck. We found all sorts
of interesting things about a complete box of lay pipes.
1.      The drill bit method was not particularly useful as a bore
measuring system, the holes were oval.
2.      The pipes had two different diameters (possibly because two
different wire prickers were used
3.      We used a travelling microscope to measue with. Although more time
consuming, certainly worth while
4.      The two bore diameters varied between means of 2.8 mm and 3.3 mm
5.      The formula used (then!) gave dates of 1614 and 1662, for a true
date of say 1655.
6.      The Friederich bowl diameter system was better giving dates
approximately 10 years too early.
Comments welcome:=}
 
Jeremy Green
Department of Maritime Archaeology
Western Australian Maritime Museum
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FREMANTLE WA 6160
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