That Birch’s ‘History of the Royal Society' (4 vols., 1756-7) is essentially a copy of the original minutes of the Council and Ordinary Meetings of the Society during the first twenty-five years of its existence is generally know n; but it is not so well known that the originals are occasionally incomplete and not infrequently inaccurate, there being no minutes of several Annual General Meetings and no record at all of some Ordinary Meetings. Hooke mentions in his diary a meeting held on 16 April 1674, at which three new Fellows were elected; the minute-book contains a blank page at this point and Birch says: ‘ The Society did not meet.’ These omissions can, in some cases, be remedied to a certain extent from independent sources, but their existence can very obviously lead to error and injustice —maybe injustice to the honour and character of some one or other of that perennially interesting group, whose words and opinions, experiments and inventions, it was the duty of Henry Oldenburg, their Secretary, to record faithfully in the minute-book.