In a large bowl, cream the butter, shortening and 1-1/2 cups sugar until light and fluffy. Beat in eggs and extract. In a small bowl combine the flour, cream of tartar, baking soda and salt; gradually add to creamed mixture and mix well.
In a shallow bowl, combine the nutmeg, cinnamon and remaining sugar. Roll dough into 1-in. balls; roll in sugar mixture. Place 2 in. apart on ungreased baking sheets.
Bake at 400° for 8-12 minutes or until lightly browned. (My oven runs hot so I lowered the temp to 375.) Remove to wire racks to cool.