Worthy, but to be honest, a little dull. Clarke has written a couple of the key works on sf of this period, and this collection brings together 14 short stories anticipating developments in warfare between the Franco-Prussian war and Sarajevo 1914. Some of the best known works of the period are omitted, I suppose because Clarke has already collected them elsewhere. A couple of familiar names crop up here unexpectedly - Arthur Conan Doyle, Jack London, A.A. Milne (this last a short parody of the genre).
With relatively journalistic material like this, I tend to rate the stories (pebhaps unfairly) on their predictive ability. Jack London's tale of the Yellow Peril, wiped out by germ warfare, does not impress on this count. Conan Doyle's piece about submarines and Gustaf Janson's reflections on warplanes score well, but for me the standout story was an early one, the anonymous "Der Ruhm; or the Wreck of German Unity", published in Macmillan's in July 1871 shortly after the proclamation of the German Empire. The author correctly predicts the humiliation and collapse of Germany as a result of militarist overstretch. Of course it was rather less immediate than he anticipated, but it nonetheless happened not once but twice in the following seventy-five years.
The story in this genre I'm still looking out for is The Next Generation, by J.F. Maguire (Liberal MP for Dungarvan and later for Cork City in the 19th century). Published in 1871, it is set in an 1891 where "the UK has been much improved by steam-powered balloons and the granting of women's suffrage; romance and the explication of other meliorist reforms just this side of utopia take up the remainder of a very long book" (according to John Clute in the Encyclopedia of science Fiction). It seems rather rare though.