Solid advice

SIR – I was interested to read that Heston Blumenthal recommends adding a lump of bauxite rock to soup (report, December 2).

However, this is not a new technique: “chuckie stane” soup has been produced in Scotland for many years.

I refer readers to the story A Vegetarian Experiment, which forms part of the Para Handy tales by the late, great Neil Munroe. Ian Craig

Strathaven, Lanarkshire