Early slate and schist quarrying

[rgagne@zzzzzzzzzzz]

Hello Learning Stone folks,

I'm a folklore graduate student, working on a dissertation about an 18th-
century New England gravestone carver named Gershom Bartlett.  It's been a
fascinating subject for me--Bartlett carved over a thousand pairs of
gravestones in Connecticut, Vermont, and New Hampshire, and quarried the stone
for them, too.  As part of this project I've been trying to learn more about
the physical process of quarrying and working stone in the 1700s--which turns
out to be difficult, since to most historical archeologists and museum
people, "historical" means 1800s.

I've read about the "plug and feathers" technique of quarrying stone, but it's
my impression that this started in about 1800, after decent drills became more
widely available.  Can anyone confirm this?

Gershom Bartlett quarried his schist in Bolton Connecticut stating in 1751,
and his slate in Norwich, Vermont starting in 1773.  I believe he may have
been driving wedges into niches at the top of vertically aligned layers of
stone to split off a sheet the right thickness for a gravestone.  If
necessary, perhaps he created such a niche with a lick.  His finished stones
are from 1 to 4 inches thick.

Once he had a piece of stone, he had to shape it to a proper silhouette--for
him, straight sides, and a large arch at the top flanked by small arches for
shoulders.  The front edges of his stones are pretty clean but a bit wobbly,
and on the back side of the stone the edges are "blown out" as if they have
been shaped by heavy blows from the front.  I have seen "stone axes" in a
gravestone carvers' probate inventory, and wonder if Bartlett may have been
using something like this to shape his stones--a heavy metal axe for roughly
shaping stone.

Then Bartlett had to smooth the front side of the stones.  Compared to other
slate gravestone workers in eastern Massachusetts and Rhode Island, Bartlett
didn't smooth his stones much, but I suspect he ground sand against them under
a brick or a flat stone.

Next came ruling lines on the stone, with some sort of straightedge and sharp
metal point.

Finally came the carving itself.  Bartlett's borders are regular and
repetitive enough so that he must have marked intervals before carving them,
but his lettering and other imagery is clearly created freehand, without any
sort of stencil or strict guidelines.  The chisel marks are plain to see,
particularly in the lettering.  Slate workers tell me that one can carve 4 to
8 letters per hour, and that the old chisels needed to be resharpened
constantly, and that after many sharpenings the edge needed to be reforged by
a blacksmith.  One 18th century gravestone carver's probate inventory had
9 "writing chisels."  Perhaps the large number of chisels helped reduce the
frequency of trips to the blacksmith for reforging.

If anyone can confirm, deny, or add to this story, I'd love to hear any
comments.  And if anyone knows of good sources about 18th-century quarrying
and stoneworking, please write!

All the best--
--Rick Gagne
(now in Bloomington, Indiana at rgagne[AT]indiana.edu,
usually in Bath, New Hampshire at morsegag[AT]sover.net )