1. A Mechanical Calculator
Napier’s Bones
A Mechanical Calculator

2. by James Nickel Copyright  2006 www.biblicalchristianworldview.net

3. Copyright  2006 www.biblicalchristianworldview.net
Board 1 2 3 4 5 6 7 8 9
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4. Copyright  2006 www.biblicalchristianworldview.net
Set of Rods 1 2 3 4 5 6 7 8 9 2 4 1 6 8 3 6 1 2 9 5 8 4 7 4 8 1 2 3 6 5 1 2 3 4 6 1 2 3 4 5 8 7 1 4 2 3 5 6 8 9 8 1 6 3 4 5 7 2 9 1 8 3 4 5 6 7 2
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5. Copyright  2006 www.biblicalchristianworldview.net
Multiplying 15  5 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 5 1 2 3 4
Read 15  5 = 75
5 ones
5 + 2 = 7 tens
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6. Copyright  2006 www.biblicalchristianworldview.net
Multiplying 28  7 1 2 3 4 5 6 7 8 9 2 4 1 6 8 8 1 6 3 4 5 7 2
Read 28  7 = 196
6 ones
5 + 4 = 9 tens
1 hundred
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7. Copyright  2006 www.biblicalchristianworldview.net
Multiplying 515  4 1 2 3 4 5 6 7 8 9 5 1 2 3 4 1 2 3 4 5 6 7 8 9 5 1 2 3 4
Read 515  4 = 2060
0 ones
2 + 4 = 6 tens
0 + 0 = 0 hundreds
2 thousands
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8. Copyright  2006 www.biblicalchristianworldview.net
Multiplying  5 1 2 3 4 5 6 7 8 9 4 8 1 2 3 6 9 1 8 3 4 5 6 7 2 8 1 6 3 4 5 7 2 6 1 2 3 4 5 8 8 1 6 3 4 5 7 2
Read  5 = 249,340
0 ones
0 + 4 = 4 tens
0 + 3 = 3 hundreds
5 + 4 = 9 thousands
0 + 4 = 4 ten thousands
2 hundred thousands
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9. Copyright  2006 www.biblicalchristianworldview.net
Multiplying 976  8 1 2 3 4 5 6 7 8 9 9 1 8 3 4 5 6 7 2 7 1 4 2 3 5 6 8 9 6 1 2 3 4 5 8
Read 976  8 = 7,808
8 ones
6 + 4 = 10 tens (write 0 and carry 1)
(carried) = 8 hundreds
7 thousands
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10. Copyright  2006 www.biblicalchristianworldview.net
Multiplying 52,908  7 1 2 3 4 5 6 7 8 9 5 1 2 3 4 2 4 1 6 8 9 1 8 3 4 5 6 7 2 8 1 6 3 4 5 7 2
Read 52,908  7 = 370,356
6 ones
0 + 5 = 5 tens
3 + 0 = 3 hundreds
4 + 6 = 10 thousands (write 0 and carry 1)
(carried) = 7 ten thousands
3 hundred thousands
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11. Copyright  2006 www.biblicalchristianworldview.net
Multiplying 548,698  6 1 2 3 4 5 6 7 8 9 5 1 2 3 4 4 8 1 2 3 6 8 1 6 3 4 5 7 2 6 1 2 3 4 5 8 9 1 8 3 4 5 6 7 2 8 1 6 3 4 5 7 2
Read 548,698  6 = 3,292,188
8 ones
4 + 4 = 8 tens
6 + 5 = 11 hundreds (write 1 and carry 1)
(carried) = 12 thousands (write 2 and carry 1)
= 9 ten thousands
2 + 0 = 2 hundred thousands
3 millions
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