It starts by describing the numbered menu structure, the standard DDMMYY input for all dates....

An observation balloon, sausage-shaped and thickened at one end by small subsidiary ballonets, lifted itself, almost as though it were being hoisted by a series of pulls, out of one of the hollows beneath them […].

Then, perhaps, there may be a chance of detecting him; but it's an outside chance.

Bullock's liver will catch drummer.