Serial working.

March 1983

https://www.americanradiohistory.com/Archive-Wireless-World/80s/Wireless-World-1983-03.pdf

Page 54.

Catt railing against parallel working. This continued in personal computers, with multiple different multi-pin parallel connectors. However, in the end the industry got it right, with the USB serial cable. Except they still don’t know to send signals in both directions down a cable pair. Heaviside joked that the signals would “devour themselves like the Kilkenny cats, leaving but their tails behind”.