James Clerk Maxwell was appointed as Professor of Natural philosophy at the Marichal College in Aberdeen on April 30, 1856. In Aberdeen, Maxwell met Meshal College Dean's daughter Catherine Mary Diyoul (Katherine Mary Dewar), Catherine Elder Maxwell seven years old, beautiful, stature slightly taller than him, clear and frank. On the February 18, 1858, he wrote to Aunt Jenny and informed her of his engagement: "Dear Aunt: This letter is to tell you that I am going to have a wife." I did not fully write about her whole quality, which I felt was inappropriate; but what I want to tell you is that we need each other more than any couple I've ever seen. Don't worry, she doesn't study maths, but there are a lot of other things besides maths, and she doesn't want to win math ... so, now that you know who she is, she is Catherine Mary Diyoul (called this name so far). I heard Uncle Robert talk about (indirectly) her father, the Dean. Her mother, a high-class lady, was quiet and rigorous, but she always treated everything in a tolerant way ... This is the case. The things I've done with her have been settled and everything is well. These are guaranteed, you will know. Maxwell used verses to express his feelings for Catherine: You and I will be together in a vibrant chunchao, my spirit has been through such a vast universe? I'm going to bring my whole life into this vibrant chunchao that will truly make three of self-crossing the vastness of the world in this poem, Maxwell sincerely expressed his love. July 4, 1858 Maxwell and Catherine Marie Diyoul (Katherine Mary Dewar) (later changed to Clerk Maxwell surname as Maxwell's surname, named Catherine Clerk Maxwell, when they married, she was 34 years old-- It was an old maid in Victorian times. ) formally married, the wedding was held in Aberdeen.