The next stage saw the replacement of human labour by machines when mechanical charging systems were developed, essentially most subsequent systems, involved the use of cards with prepunched holes around the edges, one of which could be cut to indicate the date on which an item is due. The cards are arranged by call number in a single sequence. The insertion of a knitting needle through a given hole will allow all the books overdue for a given date to fall free of the bunch of punched cards. This system is characterised by inventory and date access but placed a greater burden on the borrower. A borrower had to write the borrower's name and address and the call number, author and title of a book borrowed.
The next system to be developed was the photocharge system. In this system microphotos were taken of the borrower's card, the book card and a sequentially numbered date of issue or date due slip. This due date slip contained all the necessary information about the book as well as the borrower. Nevertheless this also had many drawbacks as the availability entire information on loan transactions was limited to a roll microfilm which introduced major operations difficulties.