A full review by John Stachel, emeritus professor of physics and director of the Center for Einstein Studies at Boston University, US, appears in the June issue of Physics World.
Most physics students learn from their textbooks that in 1905 Einstein banished the ether from physics as part of the revolution initiated by his special theory of relativity. What they generally do not learn is that in 1916 he reintroduced the concept as part of the revolution initiated by his general theory of relativity. The catch is, of course, that the ether he reintroduced differed fundamentally from the ether he had banished.
This book by Ludwik Kostro - a Polish philosopher of science - rehearses the pre-1905 history of the ether, especially Einstein's early views; his anti-ether phase (1905-1916); his new concept of the ether, based on his general-relativistic theory of gravitation (1916-1924); and its modification in the course of his search for a unified theory of gravitation and electromagnetism (1924-1955).
This is essentially the same book that appeared in Italian in 1989. This English translation all too often bears out the Italian saying "traduttore-traditore" (translator-traitor). The text is replete with misprints, mistranslations and other minor errors. However, it must be noted in the author's favour that he has included an appendix with the German originals of all key passages from Einstein and others cited in the book.
In spite of these - and other - faults, the book is well worth reading, and I wish it could be recommended more wholeheartedly.