This morning’s paper mail included an envelope with an interesting visual texture, which turned out to be a tactile texture. The paper is very slightly corrugated, so the fingers vibrate when handling this envelope. Rumble strips.

Was the ad aimed at old folks losing their vision? No, it was from Beltone Hearing Aids. Makes sense, or rather unmakes senses. Both senses fade with age.

See also If humans were blind.