A cipher to contact him.

Our first triplet concerns two entire revolutions. Take care not to run in circles.

The second triplet concerns a Winchester cartridge, often with the period first instead of last. The hunt begins.

Thirdly, a quartet. The first is half as much as the second. The third is two less that the second. The fourth is one-third of the first.

Or, send an electric letter.

[firstname]p[lastname] at gmail dot com