A practical manual that teaches the measurement, layout, and construction of stairways and the use of the steel square in carpentry. The first part defines rise, run, and pitch and gives step-by-step methods for setting out straight, winding, closed- and open-string stairs, well-holes, curved turns, handrail design and fitting, and the geometrical procedures for wreaths and tangent systems, with guidance on riser and tread proportions. The second part presents steel-square specifications and many applied problems for roof and framing work, including polygon miters, common rafters, hips, valleys, and related cutting and layout techniques.