First published by Peter Davies Ltd. in 1968, my Pan version was printed in 1972. The cover illustration "is from a study by the late Brake Baldwin, reproduced by kind permission of his widow, Mrs. E.M. Baldwin." John Brakewell Baldwin (1885-1915) was a British painter, some of whose works captured life below stairs in Edwardian times.
From all accounts, the book is Powell's unflattering memoir of life in "domestic service," as it was called. It apparently provided inspiration for both the Upstairs, Downstairs and Downton Abbey TV series.
I haven't found time to read the book yet, but I'm intrigued by "the guest with hot potatoes in her cleavage." I've also asked my own valet to start ironing my bootlaces--they now look so much better!