I WOULD ask your help and that of your wide readership to see if anyone can enlighten me in a problem I have encountered.

Every year around the second week in January, I do what many others across the country also do: I make marmalade from that season’s crop of Seville oranges, enough for the whole year.

This generally entails making four batches on four separate days to complete a larder full of about 22 pints. Every year I use the same recipe, the same quantities, made by the same process over a gas hob. I have been doing this for more than ten years now, since I retired.

This year has been slightly different: the various boilings have taken twice as long as usual; the mixture has never reached the furious, frothy state that requires vigorous stirring to prevent overflow; and the marmalade has only just reached the required state to "gel".

The question is, is the gas supply this year less than it has been? The cynic in me thinks corporate greed may have reached into the recesses of our national grids and more than the usual water vapour has been added to bulk out the volume. The calorific multiplier on my gas bill never seems to vary much, if at all, over the years, so why is the strength of the gas not what it was? Or am I just getting senile?

Sandy Parker