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

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

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Usage conditions apply
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.
Currently not on view
Object Name
Physical Description
paper (sheet material)
glass (cover material)
tape (binding material)
overall:.5 cm x 32.5 cm x 29 cm; 3/16 in x 12 25/32 in x 11 13/32 in
ID Number
catalog number
accession number
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Medicine and Science: Mathematics
Data Source
National Museum of American History
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