On Feb 25, 5:24 pm, "Rupert \(W.Yorkshire\)"
wrote:

That seems a reasonable mix but it is not critical to the nearest litre.

Quite. As a relative beginner (well, ish anyway) I tend to read
instructions (in books or with purchases) quite carefully. Frankly It
makes me wonder how the poor buggers managed to grow at all before we
came along to measure everything precisely ;-)
--
Rob