2022-03-082022-03-081971https://hdl.handle.net/2152.3/11377"Maxwell's Law" 2cor. stamp depicting Maxwell's "four equations [that] summarized the knowledge of electricity and magnetism." "Napier's Law" 25c. air stamp depicting Napier's logarithms.Two stamps from The Ten Mathematical Equations that Changed the Face of the Earth series. Issued by Nicaragua on May 15, 1971.Stamp collectingPostage-stamp AlbumsNicaraguaMaxwell, James Clark, 1831-1879Napier, John, 1550-1617LogarithmsElectricityMagnetismPostage-stamp albums