This bank book comes from an era long before Internet banking and the so called paperless office. It is leather bound, stitched and on high quality paper which hasn't yellowed in the seventy years or so since it was issued by the Westminster Bank.
All the entries are carefully handwritten in pen - not biro! On the left hand page are debits and on the right, the credits.
On each new pair of pages, the amounts are carried over and then at the end of each year the balance has been calculated.
All the entries would have been copied into ledgers at the bank where the same process would have been gone through - time consuming but I have no doubt thorough and accurate.