 Morris used advertisements to promote his bar and invention . The oldest known mention of the pisco sour appears in the September 1920 edition of the Peruvian magazine Hogar . Another old advertisement appears in the April 22 , 1921 , edition of the Peruvian magazine Mundial . In the magazine , not only is the pisco sour described as a white @-@ colored beverage , but its invention is attributed to " Mister Morris . " Later , in 1924 , with the aid of Morris ' friend Nelson <unk> , the bar advertised its locale and invention in Valparaíso , Chile . The advertisement featured in the Valparaíso newspaper South Pacific Mail , owned by <unk> . By 1927 , Morris ' Bar had attained widespread notability for its cocktails , particularly the pisco sour . Brad Thomas Parsons writes that " the registry at the Morris Bar was filled with high praise from visitors who raved about the signature drink . " 
