(born 1550, Merchiston Castle, near Edinburgh, Scot.—died April 4, 1617, Merchiston Castle) Scottish mathematician and champion of Protestantism. He divided his life between attacks on the church of Rome and the pursuit of numerical calculations. On a number of occasions he urged James IV of Scotland to deal firmly with the Catholic threat. From 1594 he worked on developing secret weapons, including a metal chariot with small holes through which shot could be fired. He developed the concept of the logarithm to facilitate calculations involving multiplication, division, roots, and powers. He also introduced the decimal point as a notation for decimal fractions. The set of calculating rods he designed was a precursor to the slide rule.
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John Napier of Merchistoun (1550 – 4 April 1617) - also signed as Neper, Nepair - named Marvellous Merchiston, was a Scottish mathematician, physicist, astronomer/astrologer and 8th Laird of Merchistoun, son of Sir Archibald Napier of Merchiston. He is most remembered as the inventor of logarithms and Napier's bones, and for popularizing the use of the decimal point. Napier's birth place, Merchiston Tower, Edinburgh, Scotland, is now part of Napier University. After dying of gout, Napier was buried in St Cuthbert's Church, Edinburgh.
Napier used some of his mathematical talents for theology, as he used the Book of Revelation to predict the Apocalypse, in A Plaine Discovery of the Whole Revelation of St. John, which he regarded as his most important work. Napier believed that the end of the world would occur in 1688 or 1700. He is also sometimes claimed to have been a necromancer; however, it was common for scientifically talented people of the period to be accused of such things without basis.
In addition to his mathematical and religious interests, Napier was commonly believed to be a magician, and is thought to have dabbled in alchemy and necromancy. It was said that he would travel about with a black spider in a small box, and that his black rooster was his familiar spirit.
Napier used this rooster to find out which of his servants had been stealing from his home. He would shut the suspects one at a time in a room with the bird, telling them to stroke it. The rooster would then tell Napier which of them was guilty. Actually, what would happen is that he would secretly coat the rooster with soot. Servants who were innocent would have no qualms about stroking it but the guilty one would only pretend he had, and when Napier examined their hands, the one with the clean hands was guilty.
Another occasion which may have contributed to his reputation as a sorcerer involved a neighbour whose pigeons were found to be eating Napier's grain. Napier warned him that from now on he intended to keep any pigeons found on his property. The next day, it is said, Napier was witnessed surrounded by unusually passive pigeons which he was scooping up and putting in a sack. The previous night he had soaked some peas in brandy, and then sown them. Come morning, the pigeons had gobbled them up, rendering themselves incapable of flight.
Also of note is that a contract still exists between John Napier and one Robert Logan of Restalrig to search Fast Castle (by means of magic) for treasure allegedly hidden there, and wherein it is stated that Napier should
"...do his utmost diligence to search and seek out, and by all craft and ingine to find out the same, or make it sure that no such thing has been there."