printing whereof and musick, has been
my chiefest employment), I have observ'd
two things many times the cause why
Books of this nature appear abroad not
so correct as they should be; either 1
Because they are too much hastened from
the Press, and not time enough allowed
for the strict and deliberate examination
of them; which in all books ought to be
done, especially in these, for as much as
one false figure in a Mathematical book,
may prove a greater fault than a whole
word mistake in books of another kind.
Or, 2 Because Persons take Tables upon
trust without trying them, and with them
transcribe their errors, if not increase
them. Both these I have carefully avoided,
so that I have reason to believe (and think
I may say it without vanity) there never
was Tables more exactly printed than in
this Book, especially those for money and

annuities, for not trusting to my first
calculation of them, I new calculated every
Table when it was in print, by the first
printed sheet, and when I had so done
I strictly compared it with my first calculation.''

De Morgan registers the nineteenth
edition of this book, dated 1756, in his
_Arithmetical Books_, and he did not apparently