A most leisurely 1977 round-the-world cruise on one of the last American passenger ships, the Pacific Far East Line's Mariposa--recalled by a passenger, mystery writer John D. MacDonald, and quipping, irreverent Captain John H. Kilpack. The Mariposa and her sister ship the Monterey would soon be out of service due to lack of government subsidy--understandably, to MacDonald: what congressman would see a political advantage in supporting ships ""toting predominately elderly Americans from island to island and from shore to shore""? While Kilpack throws up a near-inexhaustible spray of anecdotes, mostly humorous--memories of cut-ups and eccentrics and melees (the standout: a lengthy slugging match between two huge Indian lesbians), fulminations against officious on-shore officialdom, poop on navigational near-misses--MacDonald scans both shore and ship. Apropos of San Juan, from shipboard: ""A cruise is a sanitized affair. We see the barrio from afar. . . . [It's] a trip of what used to be, a voyage by twilight people in obsolete ships."" On shore, he's relieved to leave Russia, where among the ""instant old buildings"" and uncommunicative people, ""you spend hours in a kind of unfocused society."" He takes snappish, Francophobic satisfaction in rapping a line-charging Frenchman with an umbrella. He's blunt--the spic-and-span image notwithstanding--on the ""black filth"" of Dutch canals: by comparison, ""Venice with its flotillas of dead rats is a twinkling paradise."" There are pleasures, too--scenery, food, agreeable natives--and MacDonald and the Captain both give highly entertaining accounts of the major snafu: the break-off of half the rudder en route to the Virgin Islands. Eventually the Mariposa buckets home, to weary contentment: ""we had now become a village, a web of social structure."" Spottily diverting, then, for the unhurried, Emily Kimbrough audience.