WHAT WE SOMETIMES forget about empire is what enormous fun it could be. And obligatory fun, in a higher cause. I mean, could you imagine, in these air-conditioned days of package tours down the Limpopo, a bunch of fellows being required, in the name of the Queen and in the defence of 'All We Hold Dear', to poop off to Africa at its genuinely darkest with two armed ebony boats, each 40 foot long and capable of 19 knots, with orders to sink an enemy ship of 120 foot, maximum speed 7 knots, which was dominating the waters of the longest lake in the world? And, in order to get there, having to transport the said motorboats (in to& secrecy, obviously) 8,000 miles from Tilbury to Cape Town, 2,000 miles from Cape Town to Katanga, south-eastern Congo, 150 miles through virgin jungie and bush and over a 6,000-foot mountain, 100 miles along a scarcely charted stretch of the river Congo's Lualaba tributary, and through a final 180 miles of bush away to the lake shore?

Why, this was just the sort of assignment that might have come the way of our grandfathers in their guardianship of one third of the territory of the globe, its ancillary waters and its inhabitants - the bulk of them benighted natives in ardent need, whether they knew it or