by John Slater
My word, this meeting was fascinating for its content and clear presentation of, what could have been, a complex topic. The cream on the cake was, what could be a technical first for the Centenary Centre, in the second half. More, anon!
Dave Martin spoke to us about LiDAR. This form of surveying has been in use for a number of years in Britain by organisations such as Time Team on TV but coverage on the Island is recent and very exciting. Basically, lasers and radar are used either from fixed points on land or from the air, via aircraft or drones. Structures can be examined with millimetre accuracy whether as undulations on the ground or close up surface details. The accompanying pictures were of very high quality and impressive. One showed the presence and height of plants in a greenhouse all from the air. Not many secrets now!
Growing up in Knock y Doonee Farmhouse. Andreas with a Viking ship burial excavated in 1927 on one side and the remains of a keeill – an ancient chapel on the other, influenced Dave to such an extent that a childhood passion has developed into a lifetime profession supported by considerable technical skill.
It was pointed out that archaeology is frequently an invasive discipline so that the original can be left disturbed or lost to future generations. We are all familiar with the removal of items of value and interest from burials. Tomb robbers apart, even with careful recording, removal and display in museums, gain in one direction might be a loss in another. The increasing use of radar, x-rays magnetic devices can remove the risk of unnecessary disturbance and still provide valuable evidence. Somehow, I feel uneasy about removing items from a grave if the occupant and those who buried them firmly believed that they would be needed in the afterlife. We attended a friend’s funeral, on the island, not long ago to see a packet of his favourite tobacco, cigarette papers and a lighter buried with him. One hears of others with fully charged mobile phones beside them. These burials may be viewed by future archaeologists with interest and bemusement!
The Americans have scanned the whole planet with LiDAR. We saw the island in fiendish accuracy. Presumably, any of us outside at the time were also scanned!
In the second half of the presentation we collected 3D glasses and viewed a whole range of objects scanned by LiDAR. Surely a first for us gobbags! It was useful being able to see multiple faces of objects in such fine detail. We learned about the scanning of Manx crosses to determine deterioration of surfaces so that conservation measures can be considered.
One memorable quote from Dave, when talking about searches for ancient remains was, “Absence of proof is not proof of absence.” This can certainly be true for science and possibly for theology as well.
Our next meeting is on Wednesday, November 21st in the Centenary Centre at 7.30pm when detectorist, Rob Middleton talks about history beneath our feet. This local star is unmissable!