- Crossing David Thompson’s early days (washingtonlandscape.blogspot.com)
Traveling to see family, we had a stop over for a few days in London. During a walk about I spotted this plaque noting that David Thompson had attended this school. Thompson followed the upper drainages of the Coulmbia River down to the Paficic Ocean. By every account I have read of him he was a very fine fellow. I am sure the school and the neighborhood has changed a bit since the late 1700s, but it was a pleasant surprise to walk another part of his life path.
- Chert (Wikipedia)
Chert (/ˈtʃɜːrt/) is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide (SiO2). Chert is characteristically of biological origin, but may also occur inorganically as a chemical precipitate or a diagenetic replacement, as in petrified wood.