As scientists urgently call for studies on the potential health effects of microplastics that make their way into our bodies, we still don't have any easy and effective way of detecting and identifying the smallest of these polluting particles.
Electronics mystery: What is this device? I've had this for at least 10 years, and I don't know what it is or what it does.
The front-facing PCB has two opto-elements in clear T 1 3/4 packages, which appear to face through lenses that go on the front. The plate with the lenses also has a red LED. There's a dark gray cover that goes in front of the lenses.
William Wells Brown, American writer who is considered to be the first African-American to publish a novel died #OTD in 1884.
In 1847, he published his memoir, the Narrative of William W. Brown, a Fugitive Slave, Written by Himself. His first novel, entitled Clotel, or, The President's Daughter: A Narrative of Slave Life in the United States, was published in London in 1853. via @wikipedia
Books by William Wells Brown at PG:
https://www.gutenberg.org/ebooks/author/135