 Chrystal Macmillan ( 13 June 1872 – 21 September 1937 ) was a Scottish Liberal politician , barrister , feminist and pacifist , and the first female science graduate from the University of Edinburgh as well as that institution 's first female honours graduate in Mathematics . She was an activist for women 's right to vote , and for other women 's causes . She was the first woman to plead a case before the House of Lords , and was one of the founders of the Women 's International League for Peace and Freedom . 
