In what year did ARPANET carry its first message and Unix development begin?

1969 → tub · ship.

On 29 October 1969, ARPANET sent the first host-to-host message (an attempted "login" that crashed after "lo") between UCLA and Stanford — the ancestor of the Internet. Unix's development at Bell Labs also began in 1969. Peg 19 · 69 → tub · ship: a toy ship in a bath tub.