Another element of this style is the corbels under the arms of the chair, this is also a mixture of function and style, they support the overhanging arm and add mass to the front of the leg. I think as woodworkers we can all agree that a few inches of inch thick quartersawn white oak has sufficient strength to support a couple of inches of overhang, but I think you'll also agree that without the corbels the chair would look unfinished. Gustav used a short corbel and his brothers (L&JG) used a more refined, long tapered corbel.
The chair is adjusted using a nicely shaped movable peg as apposed to the later L&JG chairs that use a movable bar, more later on that chair. It also uses a similarly shaped peg for the pivot. In this photo you can also see that the crossmembers are pinned tenons, again, probably not necessary for the weight it carries but a nice touch of visible joinery. The early Gustav Stickley chairs as you can see in the above reproduction and in the picture below use a woven rope seat with a loose cushion where as those after about 1909 and those of L&JG (below)employ a spring seat.
Two features that make this chair extremely comfortable are the Bow arms, radiused at 72 inches, and the slanted seat (approx. 3 inch drop) that you can see on the left. This gives the seat a very comfortable feel and tends to snug you down into the cushion.
The front, side, and back rails are arched slightly to give this simple design lift and interest. The back reclines from almost straight up to very laid back. Add a foot stool and you've got a great napping chair with arms wide and flat enough to hold a laptop or a dinner plate.
The back slats are bent at a 36 inch radius to add to the comfort, while the original chairs and many reproductions are steambent, I find that I prefer to resaw and laminate the bend on a form. Notice the beveled ends on the seat back, another nice little detail. Some people have said in forums that flat slatted backs are just as comfortable and far easier, I have to say that I used this method on my first two morris chairs and I was less than impressed with the results compared to the curved slats. As with anything in furniture making, the devil is in the details, but then, so is the delight.
One thing I want to point out with this picture from the original chair is the grain, notice that the side is planesawn, whereas the front is quartersawn. Early Stickley chairs use this solid leg method and later Stickley furniture use quartersawn veneers to hide the planesawn surface, but there was a problem, the veneers tended to peal off from the bottom of the leg. Leopold Stickley came up with a solution to maintain the quartersawn appearance on all four sides of the leg yet still be durable, he called it the "quadralinear leg". It consists of four mitered pieces of Quartersawn white oak filled with a square middle. This five piece leg lent itself well to factory production but not having a large shaper makes it difficult for the home woodworker. You could miter and the sides and glue it up, a method I've struggled with with mixed results, no matter how careful you are with setting up the table saw and gluing you still get some gaps in the finished leg. I've also tried the miterlock router bit, but the set up is very tedious and its taking a huge bite out of some very hard wood, I've abandoned this method as too dangerous for my taste. The easiest way is to use solid legs like Gustav, but if you don't have access to 12/4 oak, you can still glue up a few pieces of 4/4, a method used on some of the originals and just as valid today. The nest time I build a Morris chair, and I've made 6 already, I'm going to attempt the original Leopold Stickley method on the tablesaw and I'll post a series of pictures and a discussion.
If you are interested in making your own Bow-Arm Stickley Morris Chair, a fantastic plan that is historically accurate can be found in Robert Lang's More Shop Drawings for Craftsman Furniture and a large format plan can be purchased separately from his site http://www.craftsmanplans.com/ .