''Music Of The Four Countries'' runs the collective title. ''Five surely?'' some would say, for where the Scottish composer writes about a Scottish subject, the Irish about an Irish subject, and the Welsh about a Welsh subject, the undoubtedly English composer writes about an undoubtedly Cornish subject: not quite, really, the same thing. The music itself, happily, cheerfully overcomes all these barriers; listeners of goodwill do not need to claim any particular allegiance, or indeed any allegiance at all, in order to enjoy it. Ethel Smyth's The Wreckers flits rather frome one mood to another; but it works excellently in the theatre. Harty's With the Wild Geese tone-poem is surely mis-titled (it is about battles and fighting: but who would guess?); it is also surely marvellously scored, exceedingly effective. MacCunn's The Land of the Mountain and the Flood (couldn't he have left out the second and third 'the'?) today needs no exposition, thanks to its use on TV some years ago. And, finally, Edward German's Welsh Rhapsody: somewhat ponderous (and very long) in its treatment of innocent Welsh tunes; but always beautifully scored. Together with the other music it is beautifully played, and well recorded. Indeed, all five nationalities concerned can enjoy all the music famously; so can another 500 nationalities if they so choose.'