--------------+-----------+---------- | | o -||--o-o------+--o-o-o-o--+--o-o----- | o | -----o--------+--o-o-o-o--+--o------- o | o | o -----o-o-o----+--o-o-o----+--o-o----- o | o | o -----o-o-o-o--+--o-o-o----+--o-o----- [*119a] Nowe to trye whether that su{m}me be well added or no, I wyll subtract one of the fyrst two su{m}mes from the thyrd, and yf I haue well done y^e remayner wyll be lyke that other su{m}me. As for example: I wyll subtracte the fyrste summe from the thyrde, whiche I set thus in theyr order. --------------+---------- | o -||--o-o------+--o-o----- | -----o--------+--o------- o | o -----o-o-o----+--o-o----- o | o -----o-o-o-o--+--o-o----- Then do I subtract 2000 of the fyrste summe fro{m} y^e second su{m}me, and then remayneth there 5000 thus. -------------+---------- | o -X-----------+----------- | ----o--------+--o------- o | o ----o-o-o----+--o-o----- o | o ----o-o-o-o--+--o-o----- Then in the thyrd lyne, I subtract y^e 100 of the fyrste summe, fro{m} the second su{m}me, where is onely 100 also, and then in y^e thyrde lyne resteth nothyng. Then in the second lyne with his space ouer hym, I fynde 80, which I shuld subtract [*119b] from the other su{m}me, then seyng there are but only 70 I must take it out of some hygher summe, which is here only 5000, therfore I take vp 5000, and seyng that it is to moch by 4920, I sette downe so many in the seconde roume, whiche with the 70 beynge there all redy do make 4990, & then the summes doth stande thus. --------------+-------------- | -||-----------+--o-o-o-o----- | o --------------+--o-o-o-o----- | o --------------+--o-o-o-o----- o | o -----o-o-o-o--+--o-o--------- Yet remayneth there in the fyrst su{m}me 9, to be bated from the second summe, where in that place of vnities dothe appere only 7, then I muste bate a hygher su{m}me, that is to saye 10, but seynge that 10 is more then 9 (which I shulde abate) by 1, therfore shall I take vp one counter from the seconde lyne, {and} set downe the same in the fyrst [*120a] or lowest lyne, as you se here. -----+-------------- | -||--+--o-o-o-o----- | o -----+--o-o-o-o----- | o -----+--o-o-o------- | o -----+--o-o-o------- And so haue I ended this worke, {and} the su{m}me appereth to be y^e same, whiche was y^e seconde summe of my addition, and therfore I perceaue, I haue wel done.