Sheet, Explanation of the Perpetual Box-Almanack and Geographical Mirror


This paper sheet is stored between two pieces of glass, with tape around the edges of the glass. It provides instructions for finding the day of the week for any date of the year, the time at different places on earth knowing the time in London, the astrological signs for different days of the year, and the phase of the moon using a specific instrument. This instrument is a combination perpetual calendar and horizontal sundial. For an example, see catalog number 330845.

Location: Currently not on view

Subject: MathematicsTimekeeping


See more items in: Medicine and Science: Mathematics


Exhibition Location:

Data Source: National Museum of American History

Id Number: MA.330846Catalog Number: 330846Accession Number: 305777

Object Name: sheet

Physical Description: paper (sheet material)glass (cover material)tape (binding material)Measurements: overall: .5 cm x 32.5 cm x 29 cm; 3/16 in x 12 25/32 in x 11 13/32 in


Record Id: nmah_1214925

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