Seeing there is nothing that is so troublesome to mathematical practice, nor that doth more molest and hinder calculators, than the multiplications, divisions, square and cubical extractions of great numbers ... I began therefore to consider in my mind by what certain and ready art I might remove those hindrances.

In computing tables, these large numbers may again be made still larger by placing a period after the number and adding ciphers. ... In numbers distinguished thus by a period in their midst, whatever is written after the period is a fraction, the denominator of which is unity with as many ciphers after it as there are figures after the period.

*Constructio *

*Hic liber est minimus, si spectes verba, sed usum
Sid spectes, Lector, maximus hic liber est
Disce, scies parvo tantum debere libello
Te, quantum magnis mille voluminibus*
The use of this book is quite large, my dear friend

No matter how modest it looks,

You study it carefully and find that it gives

As much as a thousand big books.

Opening of