James Gregory blue plaque

This blue commemorative plaque records: Gregory's Meridian Line. James Gregory (1638-1675) was the first Regius Professor of Mathematics at the University of St Andrews and an early Fellow of the Royal Society. he used the upper hall of this building, known as the King James Library, as his laboratory from 1668-1674. A north-south meridian line was laid down in the floor of the library in 1748 (continued here across the pavement). Gregory, along with Newton and Leibniz, was one of the founders of calculus. He wrote the first textbook on the subject, and calculus was taught at St Andrews 100 years before it was on the curriculum at the University of Cambridge. Gregory is also remembered for his discovery of the diffraction grating by using a bird's feather, and for his invention of the 'Gregorian' telescope, which is still in use today. This meridian line was set in place thanks to the support of St Andrews and the St Andrews Preservation Trust's Gordon Christie Bequest. Recorded plaque organisation: The University of St Andrews.

James Gregory (1638-1675), a prominent mathematician and astronomer, was instrumental in the development of calculus and invented the Gregorian telescope, significantly impacting both fields. At St Andrews University, he established early teaching of calculus and conducted pioneering optical experiments, including the discovery of diffraction grating using a bird's feather.