Wikipedia:Reference desk/Archives/Miscellaneous/2018 July 11

= July 11 =

Ancient inscriptions in masonry
In many walls or steps that were built out of repurposed stone post-antiquity, one can see inscriptions of an emperor’s dedication of a temple or some such. Of course you can only see that bit if the correct facet faces out. Are there deep-imaging methods which could read an inscription that’s faced the other way, similar to how we can find old paintings behind newer ones? If so, are there any antiquarians doing such work? Temerarius (talk) 02:30, 11 July 2018 (UTC)


 * Short answer: no. What you're referring to would be a combination of Remote sensing (though our article is rather unevenly written) and 3D scanning. The closest thing we have to that is ground-penetrating radar, but current technology is not anywhere close - just check out the pics in that article. What you get with current technologies are "discontinuities" - oddities in the read-out - that an expert uses to interpret what's going on. Maybe it's a feature, maybe it's rock. Current usage is to use it over an extended area to get a "feel" for what might be artificial. Current 3D scanning requires line of sight. Matt Deres (talk) 21:36, 11 July 2018 (UTC)


 * You can't image it with so many gamma rays that even inscriptions are enough to cause statistically significant transmission increase? Sagittarian Milky Way (talk) 22:57, 11 July 2018 (UTC)
 * Long answer: any of the many technologies for tomographic imaging may be applicable, limited by access, costs and equipment power. For example, inscriptions on fragments of the Antikythera mechanism have been found by 3-D radiographic scanning, and muon tomography by the Scanpyramids project suggests a previously unknown "Big Void" in the Great Pyramid of Giza. DroneB (talk) 23:38, 11 July 2018 (UTC)
 * Not seeing the reverse faces, but Laser scan uncovers Stonehenge secrets may be of interest. Alansplodge (talk) 08:35, 14 July 2018 (UTC)
 * Ultrasonic imaging may be of use to see the reverse side of a stone. Graeme Bartlett (talk) 00:38, 15 July 2018 (UTC)