This is, if not an official, at least a semi-official history of the Tank Corps; and if the other arms of our fighting forces get histories as good they will be fortunate. It contains the whole story of the machine and of those who manned it--invention, manufacture, organisation, training, use--from the nebulous beginnings in the minds of the various gentlemen whose claims to paternity are now being disputed to the last battle of 1918. The information has an air of final authority: official reports are backed with copious personal narrative. There is no attempt at fine writing; the book is a long series of short paragraphs containing essential facts. Yet, when occasion demands, the authors' terse sentences are far more vivid and more full of emotion than are the elaborate pages of the professional battle-painters. This is never more noticeable than in their chapter on the "Battle of Cambrai," where the fortunes of the whole Tank experiment were at stake. Nothing is elaborated, yet we see very vividly the whole panorama of those days of intense surreptitious preparation, and the final overwhelming advance against the enemy, whose suspicions had been aroused too late. The authors finally dispose of the story that the General's last order to his Tanks told them to "do their damnedest." "That spurious fosterling he hated the more the more he perceived its popularity." The authentic Order is given: a brief restrained document ending "5. I propose leading the attack of the Centre Division." This he did, in the "Hilda," which reached the outposts line in the van of the battle, General Elles standing with his head through the hatch picking up targets for the gunners. The "Hilda's" flag was several times hit, but not brought down. It was at this battle that sixteen Tanks were knocked out by one gun, served single-handed by a German officer, who died at his post. The story of the Tanks that crossed a canal on the back of another does not seem to be verified. The authors' conclusion is that "in the phase at which military science has arrived, and at which it will probably remain for a generation, a superior force of Tanks can always top the scales of the military balance of power." The illustrations are many and well chosen. We recommend the book, both as a work of reference and as a book to read. ABRAHAM LINCOLN: THE PRACTICAL MYSTIC. By FRANCIS GRIERSON. With an introduction by John Drinkwater. John Lane. 5_s._ net.