- Pipkin’s light bulb moment (spark.iop.org)
Early electric light bulbs gave off a harsh, glaring light. So, as a new recruit to General Electric in 1919, Marvin Pipkin had the brilliant idea to make bulbs with a frosted inner surface to give a gentler glow. His managers smiled indulgently and asked the eager young chemist to work on solving the problem.
- Pothole Falls (waterfallsnorthwest.com)
Pothole Falls, or The Potholes depending on which sign you confront, is the first of two modest waterfalls along Lacamas Creek as it flows from Lacamas and Round Lakes to the Washougal River. Round Lake is formed by a small dam on the creek, immediately below which the creek begins pounding through a sandstone gorge with all sorts of potholes in the stream bed. About 300 feet downstream of the dam lies the falls, a 50 foot wide, 15 foot tall plunge. The falls are so named because of the various potholes which punctuate the ledge, funneling the water this way and that - particularly in the warmer seasons. Unfortunately, trees block views of the falls from most perspectives along the rim of the gorge. There is one clear view amid a field a short distance downstream, particularly scenic in the spring when copious swaths of wildflowers bloom amid the grassy knoll.
- Incandescent light bulb (Wikipedia)
An incandescent light bulb, incandescent lamp or incandescent light globe is an electric light with a filament that is heated until it glows. The filament is enclosed in a glass bulb that is either evacuated or filled with inert gas to protect the filament from oxidation. Electric current is supplied to the filament by terminals or wires embedded in the glass. A bulb socket provides mechanical support and electrical connections.