Airborne Service Devised by Walter Windham in 1911
This page is the CodyCross answer for the clue below from Past and Present Tech, Group 1460, Puzzle 1 (Mechanical Calculator).
Question
Airborne Service Devised by Walter Windham in 1911
Answer
AIRMAIL
Word Meaning:
AIRMAIL — The system of conveying mail using aircraft.
Definitions from Wiktionary.