The last words of this book were written during an air
raid warning, and the drone in the distance indicated the
approach of enemy aircraft. The circumstance drew my
attention for the first time to the fact that for three
months I had continued to write about the British
Constitution in complete disregard of almost daily
prophecies from over the water that the next week was
to see its overthrow. The exercise was no bravado on my
part; it was, I suppose, the normal reaction of a con-
stitutional lawyer who has perforce to think in centuries
rather than in weeks, and for whom, therefore, im-
mediate threats fall into a historical perspective. He
has, so to speak, heard them so often in the past that
he unconsciously discounts them in the present. The
effects of the war are nevertheless evident in the book.
Some of the examples which seemed most convenient
were drawn from present experience; sometimes an
immediate controversy, such as that over secret sessions,
compelled an ancient principle to be more emphatically
stated; and it appeared desirable to include a special
chapter on war-time government.

The British Constitution is always topical, and no
apology is necessary for writing about it primarily in
relation to existing conditions. Perhaps, however, an
apology is required for writing about it at all. So many
good books have been written on the subject in recent
years that an addition to their number may appear
otiose. My first line of defence is that I was asked to
write. My real justification is, however, that for some
years I have been conducting a systematic survey of
British political institutions. The survey is by no means
completed, and if there had been no war I should have

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