The author of the Mushroom Planet series and other outreaches has ruminated long and read widely on the nature of children's literature--particularly on the characteristics of fantasy and its creators. The extended essays here, some published in a briefer form in Horn Book and elsewhere, touch also upon such writers' concerns as style and setting, but most of the many examples, in these sections as throughout, are drawn from the great fantasists--Nesbit, Potter, Boston, Grahame, Andersen. Mrs. Cameron states that she is writing ""appreciation,"" not criticism, but she notes the mechanical quality of Time Garden and expands upon the failure, for her, of The River at Green Knowe. On the whole it is the practiced precision of her intense appreciation which renders it valuable for novice and initiate alike--that and the fact that she extends it to current writers like Curry (The Sleepers), Mayne (Earthfasts), Clarke (Return of the Twelves), etc. The title essay, exploring the concept of Timelessness under the umbrella of time fantasy, is particularly acute. Included are revealing glimpses of the gestation of her own books and two lengthy portraits--of Wanda Gag and Eleanor Farjeon. As a tribute it is both respectful and urgent.