of the rarest of
human qualities. Even an approximation to it is rare, and absolute
accuracy is still rarer. Beware of the person who is sure of every
thing--who retails to you a conversation he has heard, affecting to give
the exact words of a third person, or who quotes passages in verse or in
prose, with glib assurance, as the production of some well-known writer.
The chances are ten to one that the conversation is mainly manufactured
in the brain of the narrator, and that the quotation is either not
written by the author to whom it is attributed, or else is a travesty of
his real language. It is Lord Byron who tells of that numerous class of
sciolists whom one finds everywhere--

"With just enough of learning to misquote."

The books one reads abound in erroneous dates, mistaken names, garbled
extracts, and blundering quotations. So much the more important is it to
the librarian, who is so continually drawn upon for correct information
upon every subject, to make sure of his facts, before communicating them.
When (as frequently happens) he has no way of verifying them, he should
report them, not as his own conclusions, but on the authority of the book
or periodical where found. This will relieve him of all responsibility,
if they turn out to be erroneous. Whenever I find a wrong date or name in
a printed book, or an erroneous reference in the index, or a mis-spelled
word, I always pencil the correct date, or name, or page of reference in
the margin. This I do as a matter of instinct, as well as of duty, for
the benefit of future inquirers, so that they may not be misled. I speak
here of errors which are palpable, or of the inaccuracy of which I have
positive knowledge; if in doubt, I either let the matter go entirely, or
write a query in pencil at the place, with the presumed correct
substitute appended.

Never be too sure of what you find in books; but prove all things and
hold fast to those only which you find to be beyond dispute. Thus will
you save yourself from falling into many errors, and from recanting many
opinions. It is the method of ordinary education to take everything for
granted; it is the method of science to take nothing for granted.

I may refer here to another rule always to be observed, and pertaining to
the theme of strict accuracy in your daily work. That is, the necessity
of carefully examining every piece of work you may have done, before it
leaves your hands, for the purpose of corre