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From Aug 2006 - Nov 2013 WeDig provided a live forum for diggers & fans of Vindolanda. It has now been mothballed and will be maintained as a live archive.

Here you will find preserved 7 years of conversation, photos, & knowledge about a site many people love. Vindolanda gets under the skin. (Figuratively and literally as a volunteer excavator!) It's a place you remember, filled with people you remember!

Thanks for 7 great years!

Viewing Single Post From: Mike's Geoblog
Mike McGuire
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One other thing I meant to add about the Whin Sill. Although the Roman masons avoided having to work this hard material as far as possible, in one place they had no option. To the east of Vindolanda along the military road, just beyond the fort of Brocolitia, is a location rather oddly called "Limestone Corner" where the wall ditch intersects the Sill. Dutifully the Roman soldiers started hacking away at the Whinstone to create a ditch through it. Amazingly they nearly completed the job. Large boulders were broken loose and pulled up out of the ditch, probably by passing ropes under them and "rolling" them up the sides. Many of these boulders are still where they were left. But one very famous boulder is still in place. This has a number of slots chisled into its surface. There is a myth commonly repeated that these are Lewis holes which the Romans intended to use to lift the boulder out of the ditch. NO - THEY AREN'T.

For a description of what a Lewis is, go to http://en.wikipedia.org/wiki/Lewis_(lifting_appliance). The Romans used the version called a "three-legged Lewis" which requires a slot to be cut in the rock in which the end faces slope away from each other as you go into the rock. There is a good example in a sandstone slab just outside the north gate of the fort at Vindolanda. But the slots in the boulder at Limestone Corner are quite different, as the the inset in the second picture below shows. In these, the short faces slope inwards. In any case, they wouldn't have cut so many Lewis holes, all at different angles and aligned along small fissures. These are quite clearly wedge holes which were to be used to split the rock into more manageable pieces. In this case they would probably have used iron wedges and some lusty blows with big hammers, although another common technique for accurate splitting of building stones was to hammer in wooden wedges and then wet them so the expansion would split the stone.

But before they got round to doing the splitting, they must have got called away to other duties, or someone said "Nobody's looking, let's not bother". In any case, they left us this fascinating insight into Roman stone working techniques. And you can now put straight anyone who says these particular examples are Lewis holes.
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Edited by Mike McGuire, Jun 15 2010, 07:29 AM.
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