M. Blundevile his exercises containing sixe treatises, the titles wherof are set down in the next printed page: which treatises are verie necessarie to be read and learned of all yoong gentlemen that haue not bene exercised in such disciplines, and yet are desirous to haue knowledge as well in cosmographie, astronomie, and geographie, as also in the arte of navigation ... To the furtherance of which arte of navigation, the said M. Blundevile speciallie wrote the said treatises and of meere good will doth dedicate the same to all the young gentlemen of this realme.

Of Addition.

WHat is Addition?

It is that which teacheth to bring many seuerall Sommes into one somme.

How is that done?

First by placing euery seuerall number one right vnder another, vnder which you must drawe a line, that done, you must adde together the numbers of the first rancke, beginning on the right

hand with the lowest figure of the same rancke, and so going vp∣ward to the highest figure of the same rancke, and so from rancke to rancke, til you come to the last, and if the Somme of any rancke doe not excéede the number of any of the foresaide 9. Digits, then set downe that Digit which comprehendeth that number right vnder his proper rancke, beneath the line, but if the Somme of that rancke, excéedeth the number of any one Digit by reason that it consisteth of Articles and Digits, then set downe the Digit and kéepe the Article or Articles in your minde, to be added to the first figure of the next rancke on the left hand, but if the Somme be an euen Article or Articles: then set downe a Cypher, kéeping the number of Article or Articles in your minde, be it, one, two, or thrée, to be added to the next rancke, all which things you shall bet∣ter vnderstand by this example here following. As for example, I spent in one yeare 125. l. in another yeare 234. l, and in another yeare 240. l. Now to knowe the totall Somme of all this, I place these seueral Sommes one right vnder another.

l

• 125.
• 234.
• 240.
• 599.

and then I drawe a line vnder them as here you sée.

Then beginning on the right hand with the lowest figure of the first rancke aboue the line, I say that a Cypher and 4. is but 4. Againe 4. and 5. maketh 9. which I set down vnder y^e line, then procéeding to the second rancke towards the left hand, I say that 4. and 3. maketh 7. and 7. and 2. maketh 9. which I also set downe, then remoouing to the thirde rancke, I say that 2. and 2. maketh 4. and 4. and 1. maketh 5. which I also set downe as you sée in the former example, so as the totall Somme vnder the line is. 599. l.

Another example hauing Cyphers mixt with Digits.

• 3047.
• 4508.
• 3049.
• 10/604.

Here I say that 9. and 8. maketh 17. and 17. and 7 maketh 24. wherefore I set downe the Digit 4. and kéepe 2. Articles in minde, which being added to the lowest figure of the second rancke, which is 14. maketh 6. then 6. and 4. maketh 10. here I set downe a Cypher, kéeping one Ar∣ticle in minde, which being added to the figure 5. of the third ranck maketh 6. which I also set downe, then I say that 3. and 4. maketh 7. and 7. and 3. maketh 10. for the which I set down first a Cypher, and then because there is no more to be added. I set downe on the left hand the one Article which I had in minde, so as the whole

Somme commeth to 10/604. as in the former example.

How are pounds, shillings, pence, halfe pence, and farthings and all other numbers of diuerse Denominations to be added?

You must deuide euery seuerall name into diuerse Collums or Spaces by themselues, and then beginning with the first on the right hand, you must adde euery Collum by it selfe, bringing far∣things to halfe pence, and halfe pence to pence, pence to shillings, and shillings to poundes, setting the Somme of euery Collum vnder the nether line as you sée in this example following.

l	s̄	d	ob.	{que}
345	13	1	0	1
234	11	0	1	1
45	14	9	1	0
320	6	8	1	1
946	5	8	0	1

Here first beginning with the Collum of farthings, I finde therein 3. farthings which is one halfe peny and one farthing. Wherefore I set downe the od farthing as you sée, and kéepe the halfe peny in minde: then adding the halfe pennie in minde to the lowest halfe pennie of the second Collum, I say that 1. in minde and 1. maketh 2. and 2. and 1. maketh 3. then 3. and 1. maketh 4. which 4. halfe pence because they make iust two pence, I set downe a Cypher kéeping the two pence in minde, which two pence being added to 8. ma∣keth 10. then 10. and 9. maketh 19. and 19. and 1. maketh 20: How because that 20. d. maketh one shilling and 8. d. I set down the 8. d. kéeping the shilling in minde, which on shilling being added to the 6. of the next Collum maketh 7. then 7. and 4. ma∣keth 11. and 11. and 1. maketh 12. then 12. & 3. maketh 15. where∣fore I set downe 5. kéeping the Article in minde, which being ad∣ded to one of the next Collum maketh 2. and 2. and 1. maketh 3. and 3. and one maketh 4. Articles, which 4. Articles maketh 40. s̄ which is two pound which I kéepe in minde, and therefore I adde the 2. l. to the Collum of pounds, saying that 2. and 5. ma∣keth 7. and 7. and 4. maketh a 11. and 11. and 5. maketh 16. wherefore I set downe 6. kéeping the one Article in mind, which being added to 2. of the next Collum, maketh 3. then 3. and 4. ma∣keth 7. and 7. and 3. maketh 10. then 10. and 4. maketh 14. wherefore I set downe 4. kéeping one Article in mind, which be∣ing added to 3. of the next Collum maketh 4. then 4. and 2. ma∣keth 6. and 6. and 3. maketh 9. which I also set downe, so as the

totall Somme amounteth to 946. l. 5. s̄. 8. d. no halfe pennie, one farthing as you sée in the former example.

How shall I know whether these seuerall Sommes be truely added or not?

Some doe teach it to be done by calling out all the nines, which way is more tedious then sure: for the surest tryall indeéde is to be done by Subtracting the seuerall Sommes out of the totall Somme, of which Subtraction we come now to speake, for all the foure speciall kindes are tryed one by an other.