Early mechanical registers were entirely mechanical, without receipts. The employee was required to ring up every transaction on the register, and when the total key was pushed, the drawer opened and a bell would ring, alerting the manager to a sale taking place. Those original machines were nothing but simple adding machines.
An early mechanical cash register was invented by James Ritty and John Birch following the American Civil War. James was the owner of a saloon in Dayton, Ohio, USA, and wanted to stop employees from pilfering his profits. The Ritty Model I was invented in 1879 after seeing a tool that counted the revolutions of the propeller on a steamship.
With the help of James' brother John Ritty, they received a patent for inventing the cash register on January 30, 1883. It was called Ritty's Incorruptible Cashier.
http://en.wikipedia.org/wiki/Cash_register
http://inventors.about.com/library/inventors/blcash_register.htm
http://www.dispatch.com/content/graphics/2013/04/01/register-timeline-art-gn2m9arh-1cashreg.jpg