Mrs. Somerville never herself introduced learned subjects into general talk, but when others did she spoke of them simply, and naturally without assuming any superior knowledge. Yet, of course, other learned people soon found out how much she knew. When she was in Edinburgh, she had written, at the request of the editor, a learned article on comets for the _Quarterly Review_, but she had no idea of writing any book till, in 1827, a letter came from Lord Brougham to Dr. Somerville asking whether Mrs. Somerville would write, for a series he was interested in, a book on a very important French work about the stars written by the famous astronomer, La Place. Mrs. Somerville had met La Place in Paris; he had said of her that she was the only woman who could understand his works, and Lord Brougham wrote that she was the only person who could write the book he wanted, and if she would not write it, it must be left undone. Mrs. Somerville writes herself that she was surprised beyond expression by this letter. She thought Lord Brougham must be mistaken as to her powers, and that it would be very presumptuous in her “to attempt to write on such a subject or indeed on any other.” However, Lord Brougham called in person to press his request, and at last she agreed, on condition that no one should know what she was trying to do, and that if she failed the manuscript should be put into the fire. She had now to try to make time for more work in her busy life. This she did by getting up earlier to see to her household duties, but she was much disturbed by interruptions. People did not think that a woman was like a man and could have any real work to do. Frequently friends or relations would arrive when she was in the midst of a difficult problem and say, “I have come to spend a few hours with you.” She had no other room to work in but the drawing-room, and as soon as the bell warned her of a visitor, she used to cover up her books and papers with a piece of muslin so that no one should know what she was doing. She learnt by habit to put up with interruptions, and to go back at once when alone again, to the point where she had left off. She did her work in the same room where her children prepared their lessons after she had taught them, and she was never impatient when they brought their little difficulties to her, but answered them quickly and quietly and went back to her own work. She could so abstract her mind that even talking or practising on the piano did not disturb her.