- PDP-11 (Wikipedia)
The PDP–11 is a series of 16-bit minicomputers originally sold by Digital Equipment Corporation (DEC) from 1970 into the late 1990s, one of a set of products in the Programmed Data Processor (PDP) series. In total, around 600,000 PDP-11s of all models were sold, making it one of DEC’s most successful product lines. The PDP-11 is considered by some experts to be the most popular minicomputer.
- United States and Canada Obsidian Source Catalog (sourcecatalog.com)
Welcome to the U. S. and Canada Obsidian and FGV (Fine-Grained Volcanic Toolstone) Source Mapping Project home page. For many years, we’ve been chasing down obsidian and FGV sources in the western United States and have promised that someday - when enough source information was finally available - we would begin creating maps that illustrate the geographic patterning of these archaeologically-significant prehistoric sources of natural glass and volcanic toolstone. That day has finally come and we are currently in the process of assembling and producing source maps for the western United States and Canada. Along with a few states (and provinces) for which we still lack good GIS coverages or adequate source data, we’re currently working on regional maps that illustrate the spatial ranges of several geographically-extensive sources.
- Obsidian (Wikipedia)
Obsidian (/əbˈsɪdi.ən, ɒb-/ əb-SID-ee-ən ob-) is a naturally occurring volcanic glass formed when lava extruded from a volcano cools rapidly with minimal crystal growth. It is an igneous rock.