It was back in the 1940's, as I recall it.
Eaton's Department store and Claxton's were the only two stores in Lindsay who had, what many called a "railroad system," when customers made payment for goods they had purchased.
There were figuratively miles of wire cages containing conveyor rails that crisscrossed their stores solely for the purpose of carrying small oval shaped cash boxes to a cashier upstairs in the store. This was the sole job that person had; make change, stamp the bill of sale "paid," then return the cash car to its' origin.
These little cars measured about five inches long, three inches wide and approximately three inches deep and would be snapped on to the "wire rail" at the sales clerk's station.
I was not the only person who questioned how those little cars, scurrying back and forth through the miles of conveyor rails, knew exactly where their destination was in both coming and going.
How they were able to travel so rapidly and yet never collide with the several others "cash cars" that were busily making their way to the upstairs?
In most cases the customer would only wait for three or four minutes when the car would return to its' original destination. The clerk would open it and hand over the contents (cash & receipt) to the customer.
If memory serves me correctly, the last person to fill the capacity of this special type of "cashier" in Lindsay was Mrs. May Davidson, a long-time employee of the "A.T. Claxton" department store.