In the 1930s, chronographs were all about function. They were often worn by Navy and Air Force officers who used the scales to calculate distance, speed or even heart rate. In short, they were the smartwatches of their time.
I chose the chronographs of that time for their beautiful dials. The wealth of information and the overall legibility is staggering! Those watches were technical pieces, battles were won, lives were saved thanks to the indication they provided. – DH