There wasn't much sleeping.

The band concert lasted until ten-thirty, then the three Germans who were trying to drink all the beer on board gave a nightly saengerfest that lasted until one o'clock, and then the men who wash down the decks appeared at four.

Between one and four it was too hot to sleep, so that there wasn't much restful repose on the ship until we got out of the Red Sea.
[Drawing: _We Slept on Deck in the Red Sea_] Down at the end of the Red Sea are the straits of Bab-el-Mandeb.

In the middle of the straits is the island of Perim, a sun-baked, bare and uninviting chunk of land that has great strategic value and little else.
It absolutely commands the entrance to the Red Sea, and, naturally, is British.

Nearly all strategic points in the East are British, from Gibraltar to Singapore.