Katherine Clerk Maxwell

Katherine Mary Clerk Maxwell (; 1824 – 12 December 1886) was a Scottish physical scientist best known for her observations which supported and contributed to the discoveries of her husband, James Clerk Maxwell. Most notable of these are her involvement with his colour vision and viscosity of gases experiments. She was born Katherine Dewar in 1824 in Glasgow and married Clerk Maxwell in 1858. Early life and marriage Katherine Mary Dewar was born in 1824 in Glasgow, the daughter of Susan Place and the Presbyterian Rev. Daniel Dewar, Principal of Marischal College, Aberdeen. Little of her early life appears to be recorded. When she was in her early 30s she met James Clerk Maxwell (7 years her junior) during his tenure as Professor of Natural Philosophy at Marischal College (1856–1860). Her father, Rev. Daniel Dewar developed a friendship with James which resulted in his frequent visits to the Dewar household as well as an invitation to join them on a family holiday. James announced their engagement in February 1858 and they were married in the parish of Old Machar, Aberdeen, on 2 June 1858. The couple did not have children. Scientific contribution Before and during their marriage Katherine aided James in his experiments on colour vision and gases. Katherine's observations were valuable to James' scientific work. In his publication in the Philosophical Transactions titled "On the Theory of Compound Colours, and the Relations of the Colours of the Spectrum", James records the observations of two individuals. He reveals himself as the first observer labeled J, but describes the second individual anonymously as "another observer (K)." Lewis Campbell confirms that the observer K was indeed Katherine.