This catamaran has been designed to simplify the construction, and, if a larger size than the dimensions shown in Fig. 1 is desired, the pontoons may be made longer by using two boards end to end and putting battens on the inside over the joint.  Each pontoon is made of two boards 1 in. thick, 14 in. wide and 16 ft. long, dressed and cut to the shape shown in Fig. 2.  Spreaders are cut from 2-in. planks, 10 in. wide and 12 in. long, and placed 6 ft. apart between the board sides and fastened with screws.  White lead should be put in the joints before turning in the screws.  Cut the ends of the boards so they will fit perfectly and make pointed ends to the pontoons as shown

[Illustration:  Details of the Pontoons]

in Fig. 3, and fit in a wedge shaped piece; white lead the joints and fasten well with screws.

Turn this shell upside down and lay a board 1/2 in. thick, 12 in. wide and 16 ft. long on the edges of the sides, mark

[Illustration:  Completed Boat]

on the under side the outside line of the shell and cut to shape roughly.  See that the spreaders and sides fit true all over, then put white lead on the joint and nail with 1-3/4 -in. finishing nails as close as possible without weakening the wood.  Slightly stagger the nails in the sides, the 1-in. side boards will allow for this, trim off the sides, turn the box over and paint the joints and ends of the spreaders, giving them two or three coats and let them dry.

Try each compartment for leaks by turning water in them one at a time.  Bore a 5/8-in. hole through each spreader in the center and through the

[Illustration:  Crosspiece and Rudder Details]

bottom board as shown.  The top board, which is 1/4-in. thick, 12 in. wide and 16 ft. long, is put on the same as the bottom.

After finishing both pontoons in this way place them parallel.  A block of wood is fastened on top of each pontoon and exactly over each spreader on which to bolt the crosspieces as shown in Fig. 4.  Each block is cut to the shape and with the dimensions shown in Fig. 5.

The crosspieces are made from hickory or ash and each piece is 2-1/2 in. thick, 5 in. wide and 6-1/2 ft. long.  Bore a 5/8-in. hole 3 in. from each end through the 5-in. way of the wood.  Take maple flooring 3/4 in. thick, 6 in. wide, 74-1/2 in. long and fasten with large screws and washers to the crosspieces and put battens across every 18 in.  Turn the flooring and crosspieces upside down and fasten to the pontoons with long 5/8-in. bolts put through the spreaders.  Put a washer on the head of each bolt and run them through from the under side.  Place a thick rubber washer under and on top of each crosspiece at the ends as shown in Fig. 4.  This will make a rigid yet flexible joint for rough waters.  The flooring being placed on the under side of the crosspieces makes it possible to get the sail boom very low.  The sides put on and well fastened will greatly assist in stiffening the platform and help it to stand the racking strains.  These sides will also keep the water and spray out and much more so if a 12-in. dash is put on in front on top of the crosspiece.