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Samuel Heinrich Schwabe made 8486 drawings of the solar disk with sunspots inthe period from November 5, 1825 to December 29, 1867. We have measured sunspotsizes and heliographic positions on digitized images of these drawings. A totalof about 135,000 measurements of individual sunspots are available in a database. Positions are accurate to about 5% of the solar radius or to about threedegrees in heliographic coordinates in the solar disk center. Sizes were givenin 12 classes as estimated visually with circular cursor shapes on the screen.Most of the drawings show a coordinate grid aligned with the celestialcoordinate system. A subset of 1168 drawings have no indication of theirorientation. We have used a Bayesian estimator to infer the orientations of thedrawings as well as the average heliographic spot positions from a chain ofdrawings of several days, using the rotation profile of the present Sun. Thedata base also includes all information available from Schwabe on spotlessdays.

Sunspot positions and sizes for 1825-1867 from the observations by Samuel Heinrich Schwabe