Construct an overhead framework of six by two inch spruce beams twelve feet long, and set them in the ground twelve feet apart, bracing the uprights well, braced at both sides with angle beams as shown in Fig. 23. The top bar should be well braced also with one or two angle brackets, to prevent the frame from rocking. If the ground props are not strong enough to properly brace the frame, attach heavy wires to the corners and carry them out in both directions, making the ends fast to stout pieces of joist embedded in the ground.
At the middle of the top cross-bar arrange a plate of wood eighteen inches long with a groove cut in it in which the pin at the top of the square shaft may revolve. This plate should be attached to the bar with lag screws, so that it can be removed when it is necessary to unstep the shaft and platform. The outer line of deck planking is shown in the deck plan (Fig. 28), and inside of these boards as many others can be laid down as desired; or the entire frame may be all decked over, leaving a small space near the middle so as to reach the gear and lower pin in order to grease them. Where the shaft passes one of the uprights of the supporting frame an iron strap will hold it in place against the wood, and this bearing will require lubrication from time to time.
Four stout wire guys must be drawn from the top of the shaft and fastened at the outer edge of the platform to one of the beam ends. The anchorage should be made with very stout, strong screw-eyes, and to make it easier to draw the wires taut four small turn-buckles should be purchased at a hardware store and made fast to the lower ends of the wires, the hook on the buckle being caught in the large screw-eyes.
Seats may be made from boxes and nailed to the deck, and as a safeguard to prevent falling from the turn-table ropes should be attached to the stanchion wires and to the shaft as shown in Fig. 23.
It would be well to paint all the wood-work in order to give it a good appearance, and all the iron parts should be coated with asphaltum varnish to prevent rusting.
If the gears are properly adjusted and there is no friction at the bearings, it will not be a difficult matter to move the table with several children occupying the seats. The bevelled point bearing at the bottom rests in a drilled depression in the plate, and the friction there is reduced to a minimum, while at the top the friction will be slight if the weight is properly distributed on the turn-table.
Chapter II
PET SHELTERS
Most boys are interested in pet animals, and at one time or another possess them. Cats and dogs are domesticated and will always stay about the house if they are properly cared for and treated kindly, but rabbits, guinea-pigs, squirrels, monkeys, and reptiles often forget where they belong and will wander away and neglect to come back.
For this reason it will be necessary to build houses and hutches for them, and so safeguard the doorways and screenings that they cannot escape.
It is not possible, of course, to give a lengthy description of pet shelters, since there are so many different kinds in use by boys all over the world; but the illustrations on these pages will give some ideas for the American and English boys to follow in making houses, hutches, and retreats to shelter their pet animals, birds, and reptiles.