Dear all,
I have seen plenty of these in the 'Roman' period site of Meroe in Sudan,
back in 1992. Some were clearly solidified filling / blocking the local
common tuyeres (since bits of these tuyeres were still attached to them).
The outer, low-fired ends of tuyere would have been not very resistant to
being trampled on by goats etc., and thus may have resulted in 'free' slag
rods. Some show a long conical inner hollow along the tube, as if air was
still being blown into / through the tuyere while slag was trying to come
out; others have a semi-circular cross section with a flow surface as if not
filling the tuyere fully.
There was at least one piece which then continued the slag flow with a 90
degree angle downwards, evidently along a rough surface (judging from
imprint in the slag surface facing inwards, and an open flow texture on the
outward-pointing surface) as if running down the outside of the furnace,
during tapping slag through a hole c 20 cm above ground. This seemed to come
through a hole poked through the furnace wall rather than from a tuyere
(judging from a somewhat thinner diameter compared to the tuyeres).
Sadly, most of the material is still sitting in Meroe, waiting to be
collected...
Thilo
----- Original Message -----
From: "Tim Young" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, November 17, 2009 7:52 PM
Subject: Re: slag rods/tubes on archaeological sites
> Hi David
>
> I've seen rods pretty frequently on the bloomery sites around the Forest
> of Dean area. In
> sone cases I suspect that tapping was undertaken through a fairly small
> hole in the block of
> the tapping arch - rather than having an open arch. I've seen objects that
> look like SHCs with
> a protruding rod that I think are slag bowls from the base of slag tapping
> furnaces.
>
> I've also seen true SHCs with rods - and suspect these may be from
> attempts to extract the
> cake using a stout poker - which has been pushed through the cake and down
> into
> underlying ash(?). On withdrawing the poker the slag has filled the
> cavity.
>
> Although by far the most common usually on bloomery sites, rods (and
> possibly tubes) are
> extremely common on a finery site I've been looking at - presumably with a
> similar origin to
> those proposed for the bloomery.
>
> Tim
>
>
>
>
> --
> Dr Tim Young
> Email: [log in to unmask]
> Web: www.geoarch.co.uk
> Phone: 07802 413704
> Fax: 08700 547366
>
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