From John Gray
There are other contributions to the “dirty cloud over India”: besides those you mention (9 December, p 20). These include underground fires in shallow seams of soft brown coal, which are almost impossible to extinguish – does anyone have any ideas? There are also peat fires in Indonesia, ignited during cut-and burn farming preparation and again almost impossible to extinguish. The clouds from Indonesia also envelop Malaysia and Singapore at some times of the year.
Bedworth, Warwickshire, UK
