[Illustration:  Adjustable Horizontal Bar

wood, bolts and rope, can make a first class gymnasium.  If trees are convenient, and some one can swing an axe, the money outlay will be almost nothing.  The following plans are for material purchased from a mill squared and cut to length.  To substitute small, straight trees for the squared timbers requires but little changes in the plans.

The most important piece of apparatus in the gymnasium is the horizontal bar.  Most gymnasiums have two:  one adjustable bar for various exercises and a high bar for gymnastic work.  The outdoor gymnasium combines the two.  The material required is as follows:  2 pieces of wood, 4 in. square by 9-1/2 ft. long; 4 pieces, 2 by 4 in. by 2 ft. long; 4 pieces, 1 by 7 in. by 6-1/2 ft. long; 4 filler pieces, 3/4 by 3 in. by 3 ft. 9 in. long and 1 piece, 2-1/2 in. square by 5 ft. 7 in. long.  This latter piece is for the bar and should be of well seasoned, straight-grained hickory.  It makes no difference what kind of wood is used for the other pieces, but it is best to use cedar for the heavy pieces that are set in the ground as it will take years for this wood to rot.  Ordinary yellow pine will do very well.  The four 7-in. boards should be of some hard wood if possible such as oak, hickory, maple, chestnut or ash.  The other material necessary consists of 2 bolts, 1/2 in. in diameter and 7 in. long; 16 screws, 3 in. long; 4 heavy screw eyes with two 1/2-in. shanks; 50 ft. of heavy galvanized wire:  80 ft. of 1/4-in. manila rope and 4 pulley blocks.  Four cleats are also required but these can be made of wood at home.

Draw a line on the four 7-in. boards along the side of each from end to end, 1-1/4-in. from one edge.  Beginning at one end of each board make pencil dots on this line 5 in. apart for a distance of 3 ft. 4 in.  Bore holes through the boards on these marks with a 9/15-in. bit.  Fasten two of these boards on each post with the 3-in. screws, as shown in the top view of the post Fig. 1, forming a channel of the edges in which the holes were bored.  Two of the filler pieces are fastened in each channel as shown, so as to make the space fit the squared end of the bar snugly.  The ends of the boards with the holes should be flush with the top of the post.  This will make each pair of holes in the 7-in. boards coincide, so the 1/2-in. bolt can be put through them and the squared end of the bar.

Select a level place where the apparatus is to be placed and dig two holes 6 ft. apart, each 3 ft. deep and remove all loose dirt.  The ends of the posts not covered with the boards are set in these holes on bricks or small stones.  The channels formed by the boards must be set facing each other with the inner surfaces of the posts parallel and 5 ft. 8 in. apart.  The holes around the posts are filled with earth and well tamped.

The hickory piece which is to form the bar should be planed, scraped and sandpapered until it is perfectly smooth and round except for 3 in. at each end.  Bore a 9/16-in. hole through each square end 1-1/4 in. from the end.  The bar may be fastened at any desired height by slipping the 1/2-in. bolts through the holes bored in both the bar and channel.