Then halve the second figure. This done, the seconde is to be halfede, yf it be a cifre put it be-side, and yf it be significatife, [other it is even or ode]: If it be even, write in the place of þe nombres wipede out the halfe; yf it be ode, take the next even vnder it [contenythe], and in the place of the Impar sette a-side put half of the even: The vnyte that remaynethe to be halfede, respect hade to them before, is worthe .10.

Halfede
to be halfede

If it is odd, add 5 to the figure before. Dyvide that .10. in .2., 5. is, and sette a-side that one, and adde that other to the next figure precedent as here:—

And yf þe addicioun sholde be made to a cifre, sette it a-side, and write in his place .5.

doublede2689010174
to be doublede13445587

And vnder this fourme me shalle write and worche, tille the totalle nombre be halfede.

Chapter V. Duplation.

Definition of Duplation. Duplicacioun is agregacion of nombre [to itself] þat me may se the nombre growen. In doublynge ay is but one ordre of figures necessarie. And me most be-gynne with the lift side, other of the more figure, And after the nombre of the more figure [representithe]. Fol. 51. *In the other .3. before we begynne alle way fro the right side and fro the lasse nombre, Where to begin. In this spice and in alle other folowyng we wolle begynne fro the lift side, ffor and me bigon the double fro the first, [omwhile] me myght double oo thynge twyes. Why. And how be it that me myght double fro the right, that wolde be harder in techyng and in workyng. Therfor yf thow wolt double any nombre, write that nombre by his differences, and double the last. And of that doublyng other growithe a nombre digital, article, or componede. [If it be a digit, write it in the place of the first digit.]

double10
to be doublede5

What to do with the result. If it be article, write in his place a cifre and transferre the article towarde the lift, as thus:—