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Date: | Tue, 28 Jul 1998 07:39:52 -0400 |
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Anne:
A footnote to Dan Weiskotten's last posting re: flint/chert:
While New Yorkers never appear to have selected chert of the Onondaga or
Normanskill varieties for architecture, roadbuilders use the cherty
limestone (17% chert as I recall) for crushed rock road paving. Miners
have blasted more than a few prehistoric quarries as a result.
Jim Gibb
The Lost Towns of Anne Arundel Project
Annapolis, MD USA
Daniel H. Weiskotten wrote:
>
> Anne:
> Having spent most of my life on the margin of the Onondaga Escarpment
in
> central New York State, I can say that I have seen some massive chunks of
> "flint" or chert, as we call it, in the Onondaga Limestone (Devonian), but
> I have never seen it used as an intentional architectural component. It
> occurrs in narrow beds of nodules that formed within the limestone and thus
> only by accident was it included in building stone. Some beds of chert are
> quite thick (20 - 30 cm) but, being composed of various sized nodules, are
> so irregular that you would be hard pressed tro find a big enough peice to
> comprise an entire decent sized building block. Many of central New York's
> most fascinating 19th century buildings, all of the locks on the old Erie
> Canal, as well as other massive engineering works such as dams, bridges,
> and fortifications, are made of this stone but the chert is notably absent
> from the building blocks as it was considered an imperfection and would
> have weakened the massive stones and caused them to cleave (a problem in
> the deep frosty CNY winters !) Most stones are perfectly clear of
> imperfections and can be quite large = often a meter thick and I've seen
> some 10 meters long!
> I have seen glacially rounded cobbles of chert used in the constructio
n of
> many of the region's unique 19th century cobblestone houses, but they were
> probably chosen for their dark color rather than their "flinty" qualities.
> Polished Onondaga Limestone tabletops and tombstones (obelisks) made in the
> 1840s to 1880s took advantage of the wonderful fossils that were within the
> stone and I have never seen a spot of chert. I suppose this is because the
> chert is so much harder than the surrounding matrix and usually caused a
> cleavage plane which the carvers used to their advantage.
> While working at Mount Independence (160 acres of Rev. War fortificati
on
> on Lake Champlian) with David Starbuck a few years ago I saw many wonderful
> chert outcrops but only minor inclusions in the widespread foundations and
> debris piles. Debitage piles were found at all the outcrops but fragments
> were small and the larger pieces quarried in prehistoric times would have
> been picked over by soldiers looking for good flints for their guns.
>
> Dan W.
>
> ________________________________________________
> Don't forget to check out
> DAN WEISKOTTEN'S HISTORY AND ARCHAEOLOGY WEB PAGE at:
> http://www.erols.com/weiskotten/weiskotten.html
>
> Since I'm desperate for work in the Richmond/Penninsula area, take a
> look
> at my CVand samples of my informal research and writing at:
> http://www.erols.com/weiskotten/dansvita.html
>
> also note that I have a new e-mail address:
> [log in to unmask]
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