From TOM NASH
Tam Dalyell need not be worried about the effect of nitrous oxide
on our historic buildings (Thistle Diary, 20 August). I was attending an
abbey service recently, at a time of high air pollution, and did notice
that the congregation tended to break out in giggles during the perfectly
serious sermon. This was of course due to the unusually high concentration
of nitrous oxide present. While the result was somewhat irreverent, the
stonework could not have been affected, since the gas is quite inert in
this respect. The main culprit is always sulphuric acid from the sulphur
dioxide in polluted air.
Tom Nash Sherborne Dorset
