And we both have the same black-and-white cows."" So discovered British writer Bailey (America, Lost and Found, etc.), who decided to travel the length of the Iron Curtain--from Priwall beach on the Baltic Sea to Trieste on the Adriatic--and here offers an overextended travel diary, but one that does have some substance as a political overland passage. By far the greater part of the journey takes him along the border between the two Germanys: viewing East German border-guards and fortifications with West German border-guards; learning something of East German life from West Germans who visit; reading German books by Boll, Grass, Christa Wolf; experiencing (more acutely, perhaps, than the locals) the peculiarity of being on the line that divides ""our"" cows from ""theirs."" But though there's an overblown, trivializing quality to much of this house-divided dramatizing (with little reportage that would come as news to, say, regular New York Times readers), there are occasional trans-border illuminations. A West German couple of Bailey's acquaintance makes a practice of establishing East German contacts: the wife knows how Americans must have felt after the war as she shares with the East (bringing ""things like peppercorns""); the husband tends to think of East Germans as more altruistic. (""But I wondered,"" says Bailey, ""if he didn't feel a need to compensate for the good life in West Germany by ascribing greater virtue to those who grinned and bore it in the East."") Bailey also learns, in the concrete news department, that ""many East Germans manage to leave the DDR by first going to prison and being ransomed out by the West German government""-which, however, has to guard against letting in spies as purported prisoners-of-conscience. Later, the journey itself--taking Bailey into East Berlin, and to Prague--does eventually acquire some thematic shape, when he moves into transitional Austria (where Eastern refugees are processed). . . and then, with relatively little ado, into Hungary. The Iron Curtain is porous here; there are differences--in the behavior of border guards, in the bookstores and restaurants, the whole ambience of Budapest. And, driving finally from Austria to Trieste, Bailey takes an impromptu shortcut through (communist-but-not-Comintern) Yugoslavia. Much travel-book filler, true, but also a distinct sense of distance traversed overall--with some pinpricks through the Curtain at its most severe.