ALL phenomena are wonderful in the measure that we are unaccustomed to strange to them, and if quite strange to us they are incredible. The romantic character of the details of any subject is therefore an in dividual matter, but the in this particular case assumes no exact, and little general, knowledge on the part of his readers, and so he is justified in his repeated absevrations of the marvellous character of the various details of the discovery and achievements of photography. We take it that the duty of the writer of such a volume is very largely to rob his subject of its atmosphere of romance by showing its gradual development and the reasonableness of its results. In this the author is successful. He gives no “instructions,” but merely tells his story in a readable form and illustrates it well, for every one of the sixty or more illustrations has a definite and sufficient reason for its presence. He treats it in an easy and sometimes, perhaps, rather too discursive manner, giving many apt analogies of the development of photography and of its applications in instantaneous work and kinematography, the making of book illustrations, the photography of the invisible as by means of Röntgen rays or the ultra-violet of the spectrum, and the reproduction of colour.