It is therefore better to use some independent notation, such as A Z.
Various special algebras (for example, quaternions) may be expressed in the notation of the algebra of matrices.
There is a complete edition in modern notation by T.
He prints a bar under the decimals; this notation first appears without any explanation in his "Lucubrationes" appended to the Constructio.
Briggs seems to have used the notation all his life, but in writing it, as appears from manuscripts of his, he added also a small vertical line just high enough to fix distinctly which two figures it was intended to separate: thus he might have written 63 0957379.