Multiplication notes: 7 times 7 makes 49
Number columns 1-13 worked with products of seven and the rule of the larger half
Columns of numbers running from 1 to 13 are worked with products of seven: '3 times 7, 21', '4 times 7, 28', '6 times 7, 42', and '7 times 7 makes 49.' A note states the method as multiplying the larger half by itself. The rows are keyed with the letters a, b, c and d.
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Products of seven and the 'larger half' rule
Rows labelled a and b give 3x7=21 and 4x7=28; rows c and d give 6x7=42 and 7x7=49. The rule is stated as multiplying the larger half by itself, applied to the series running from 1 to 13.