turn the wedging piece, referred to before, up on edge 

 and use this to bear the joists. The latter sometimes 

 have to be notched to bring the sheeting low enough. 

 In setting up beam and girder sides use spreaders 

 at the top made from waste strips cut as long as the 

 beam is wide to keep the top edges of the beam sides 

 the right distance apart. If a thin strip a little longer 

 at each end than the spreader be nailed to it, it will 

 keep the spreader from falling down into the box and 



FIG. 6. SPREADERS USED TO SEPARATE BEAM AND 

 GIRDER SIDES. 



may also serve to prevent the sides from spreading, 

 by tacking with a small nail through each end. Keep 

 them in place as long as possible. If taken out while 

 placing steel put back again, and keep in place till 

 absolutely necessary to remove them while concreting. 

 Various kinds of lumber are used for joists as well 

 as for sheeting. Joists are made of 2x4, 2x6 and 

 iVx8. Conditions determine the size and spacing 

 center to center. Assuming a moderate span between 

 the beams of say 5 to 7 or 8 feet and a good firm 

 decking of ?6-in. or i-in. matched or ship-lapped you 

 might use say 2 x 4 at 14-in. to i6-in. center to center, 

 or 2x6 or I T x8 at 18 in. or 2O-in. center to center. 

 This of course implies only moderate loads, i. e., a 



