To say that [An Old Magic] is a typical Ruth Arthur story, is to predicate wholesome characters of the present day who have contact with a world outside of present time and space. Here, the mysterious element is provided by gypsies on a mountain overlooking a Welsh farmhouse and their influence on the farm family through four generations. The strangeness of being a twin is another theme explored. Just occasionally the characters seem to be symbols rather than real people and one or two incidents seem slightly contrived, but such is the author's gift of storytelling that it is impossible not to read on. (p. 256)