This section is from the book "Spons' Mechanics' Own Book: A Manual For Handicraftsmen And Amateurs", by Edward Spon. Also available from Amazon: Spons' Mechanics' Own Book.
These are shown in Fig. 570. The sides (2) a may be 2 1/2-6 ft. long (high), 5 in. wide, and 1 in. thick; their top and bottom ends are bevelled, so that the finished article shall stand in a slanting attitude. The 4 steps b are 6 in. wide, 1 in. thick, and increase about 1 or 1 1/2 in. in length as they descend, i. e. supposing the topmost of the 4 to be 12 in. long internally, the lowermost might be 16 1/2 in.; this gives solidity by spreading the sides. Each of these 4 steps b is let about 1/4 in. to 3/8 in. into grooves cut in the 2 side pieces a, and secured by a few nails or screws. As the side pieces a are only 5 in. wide while the steps b are 6 in., there remains 1 in. of step projecting beyond the sides; this projection comes in front, where the step is allowed to have the full width so as to come flush with the outside of the side pieces. The top step c differs from all the others: it is long enough to have about 1 in. at each end overhanging the sides; it is about 2 in. wider than the other steps; and into it the upper ends of the side pieces a are mortised, or let into a groove and screwed.
When this half of the steps is complete, a piece of board d, about 6 in. wide, 1 in. thick, and of a shape to fit flush with the outside of the side pieces a, is firmly screwed to the back of the side pieces. To this board d is attached, by a couple of stout flap hinges, a light frame e, formed by mortising and glueing together 2 upright strips 2 1/2 in. wide by 1 in. thick and 2 cross pieces 3 or 4 in. wide and 1 in. thick, in such a manner that each upright falls at the back of one of the side pieces, while the upper cross piece comes immediately below d and receives the lower halves of the 2 hinges, and the bottom cross piece is at the level represented by the cord /, which is attached to it at one end and to one of the side pieces a at the other. The length of the frame e should correspond exactly to that of the side pieces a. The front top edges of the steps are rounded off. The distance between the steps is usually 7-9 in.