The History of which this is the first volume is, in the main, the history of the part played in the war by British air forces. It is based chiefly on the records of the Air Ministry collected and preserved at the Historical Section. The staff of the Section have spared no trouble to collect an immense amount of material and arrange it for use, to consult living witnesses, to verify facts down to the minutest details, and to correct any errors that may have crept into the narrative. Their main purpose has been to secure that any statement of fact made in this book shall be true and demonstrable. If in any particular instances they have failed in this purpose, it has not been for lack of pains and care.

Official records do not in themselves make history. They are colourless and bare. In the business of interpreting and supplementing them we have been much helped by the kindness of many military and naval officers and of many civilian experts. Their help, most of which is acknowledged in the text, has supplied us with the liveliest things in this book. We could wish that we had more of it. Naval and military officers do not advertise, and are reluctant to speak publicly of the part that they played in the war. They are silent on all that may seem to tell to their own credit or to the discredit of others, and this silence easily develops into a fixed habit of reticence. We are the more grateful to those who have helped us to a true account by telling of what they saw. The best part of the book is yet to come; if the theme is to be worthily treated, it must be by the help of those who remember and of those who know.

The writer of this history has endeavoured to make his narrative intelligible to those who, like himself, are outsiders, and, with that end in view, he has avoided, as far as possible, the masonic dialect of the services. For the few and cautious opinions that he has expressed he alone is responsible. In controverted questions, though he has not always been careful to conceal his own opinion, he has always tried so to state the grounds for other opinions that those who hold these other opinions may think his statement not unfair. If his own opinion is wrong, the corrective will usually be found near at hand. The position of an outsider has grave disabilities; if a measure of compensation for these disabilities is anywhere to be found, it must be sought in freedom from the heat of partisan zeal and from the narrowness of corporate loyalty. Some of the men who early took thought for their country's need, and quietly laboured to prepare her against the day of trial, are here celebrated, and their names, we hope, rescued from neglect. The men who flew over the fire of enemy guns were so many that comparatively few of their names, and these chosen almost by accident, can here be mentioned. There were thousands of others just as good. The heroes of this story, let it be said once and for all, are only samples.

Some apology perhaps is necessary for the variety which has been found inevitable in naming particular men. A man's christian name and surname are his own, but change and promotion were rapid during the war, so that the prefixes to these names varied from year to year. Where we are describing a particular deed, we give the actors the rank that they held at the time. Where we speak more generally, we give them the rank that they held when this history was written.

WALTER RALEIGH.