48 AERONAUTICS IN RELATION TO NAVAL ARCHITECTURE. 
on smooth or rough water. All straight V’s throw a strong sheet of spray at the 
bow. This sheet of spray appears to be independent of the true bow wave. It can 
be suppressed by the use of hollow V-lines at the bow, but this form is difficult to 
build strongly and has bad steering tendencies when trimmed by the bow or when 
making a skidding landing or get-away. A simpler method of suppressing this bow 
spray is the use of mud guards, so-called for obvious reasons. 
The V-bottom also greatly reduces the danger of sticking a wing under on a 
skidding landing, or when running at high speed across the wind. 
The use of fine lines at the bow or stern is not very general, because of the need 
of longitudinal stiffness. Such lines steer badly, and there is some evidence of the 
suction effect being present. It is not improbable, however, that a compromise be- 
tween such lines and the V-bow may work out in solving the seagoing problem. 
In construction details in this country the boat-builders’ influence is just being 
asserted. The principal builders have followed a box-like construction not dispos- 
ing of their material to advantage. 
In recent efforts to develop a stream-line form of float, embodying as much as 
practicable the requirements enumerated, the following features have been devel- 
oped :— 
Plate 34 shows views of these floats in different stages of construction. The 
general form is as nearly stream line as practicable, having a curved deck comprised 
of two-ply spruce, applied diagonally, one across the other, with cotton sheeting and 
marine glue between the plies. This construction eliminates the usual deck joints 
and provides the arched form with diagonal bracing, continuous from chime to 
chime. 
Through the center of the float a longitudinal truss provides the backbone of 
the construction. Two-ply bulkheads support the float attachments, and the prin- 
cipal bulkheads are tied to each other and to the step by a two-ply fore-and-aft bulk- 
head built into the center-line girder. These bulkheads are bound by oak ribs and 
intermediate ribs of oak support the top shell. 
The bilge stringers and the keelson are continuous, the step being formed by 
tapered liners. The step is of oak, as when grounding, or when planing at high 
speed, the loads are concentrated at the step. The bottom is two-ply spruce, the 
inner ply running athwartships and the outer ply running diagonally outboard and 
aft from the keel to the bilge stringers. 
Cotton sheeting and marine glue are used in all two- “Oy work and the plys are 
held together by special clinch nails of brass.” 
The bottom is supported by the keel and bilge ieee and an intermediate lon- 
gitudinal, which are in turn supported by the step and bulkheads. The stem and 
stern pieces are of spruce, shaped to take the longitudinal members and rabbeted to 
receive the shell planking. The system of bottom planking and longitudinals elimi- 
nates the use of bottom frames and really provides continuous framing in the plank- 
ing itself, similar to Hands’ original V-bottom construction. This type of bottom 
planking appears resilient and strong. 
