THE author of “Submarines” is to be congratulated on having produced a well-written book upon a subject which has become of the greatest interest to a large world of readers. He tells Us that this is not a technical book, and a doubt might aiise lest it should in consequence be devoid of any clear or exact information, but this is not the case. The subject is so new and is so little understood that the excellent exposition of the whole subject to be found in the pages will, without doubt, command a large and immediate success. It would be difficult to: expend the moderate price of 3s.6d. to better account if making a present to any boy with an active mind, and the boy -need not be so very young1 or the mind so very active—it is not written for boys—for,fhe reader, to be absorbed in interest.