This notebook covers the period January 1891-April 1892. It was used by an unidentified experimenter, probably William K. L. Dickson, for notes, drawings, and calculations regarding iron ore separation experiments. Among the samples tested are ores from the Ogden mine, site of Edison\'s New Jersey and Pennsylvania Concentrating Works, and from the Spurr mine in Humboldt, Michigan. The pages are unnumbered. Approximately 20 pages have been used.