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Trains and vertical motions of the wheels and axes of the right, middle and left groups of Plan 28a for division as performed in working Notation 290. Sheet 1 of 4.
Addition and subtraction. Multiplication by stepping without table (to be done in store). Division by powers of ten (stepping done in store).
First arrangement of the verticals for one barrel to do approximative multiplication. Notation 268. Sheet 1 of 2.
Reversing sign ascertaining if a variable is zero, ascertaining if a variable has a + or - sign (supersedes 223).
Vertical movements of axes ordered by right barrel for multiplication compiled in part from a genealogical notation. Sheet 1 of 3.
Letter from Sir John Barton to "Commissioners appointed to consider the means of preventing the Forgeries of the Notes of the Bank of England"