DEEP-SEA EXPLORATION. 
263 
Bull heads : One collision water-tight bulkhead about 25 feet from the stem ; one 
at the after end of the forehold, connected by deck plates as shown ou the plan; 
one forward of boilers, connected by iron deck; one between the engines and boilers; 
a water-tight compartment abaft the engines between the shafts, the after end 
extending to the after collision bulkhead, which is at the forward end of the stern 
pipes; it is attached to the cVoss keelson which sustains the stern pipes, and extends 
to the berth deck with a plate-iron covering over the beams so as to make the after 
compartment entirely water- tight; the other bulkheads extend from the floors to the 
main-deck beams. Bulkheads are of 1 % iron butt-joints; strakes run in one length 
from floors to deck beams, 30 inches wide. The lap strips of joints are of T iron, 3^ 
by 3 by n, inches; laps single-riveted with | rivets. The after collision bulkhead has 
recently been extended up to the main deck. Sluice valves are provided; bilge 
suction-pipes from the several compartments connect to a manifold in the engine 
compartment, and each pipe has a foot valve. 
Ir' 07 i declc-house: The sides of the midship deck-house from the after end of the 
house to the bulkhead forward of the funnel, including these two bulkheads, are of 
plate iron, No. 5 wire gauge; stanchions, of 3 by 3 inches, angle-iron, spaced 24 inches 
from center to center. The beams are of angle-iron, 3 by 3 by {hi inches, riveted to 
stanchion and to stringer and hatch-plate below. 
Plating: The plating is run in fair lines, in and out strakes; all horizontal seams 
are lapped and all vertical seams, including bidwarks, are butted; spaces between 
outer strakes and frames are filled with liners of iiroper width and thickness. 
The garboard-strake is -j-§ inch thick for three-fifths its length amidships, gradually 
reduced to inch at the ends, and is 32 inches wide. 
Sheer-strakes are fayed next to frames, y-g inch thick for one-half the length 
amidships, gradually reduced to -j% inch at the ends, and 38 inches wide. The upper 
edge extends 3^ inches above top of plank-sheer to connect bulwark plates. 
Bulwark plates from sheer-strake to rail aie inch thick, well riveted to 
sheer-strake and frames. Along the whole length of the upper edge of the bulwark 
plates, ou the outside, is run an angle-iron, 3^ by 34 by | inches, well riveted to 
bulwark plates, with proper lap-strij)s at the butts. To this angle-iron the rail is 
fastened. 
The side-strake next below the sheer-strake is f inch thick at midship length, 
gradually reduced to -{,■ inch forward and aft. The remaining side xilating is inch 
thick, except the strakes around the shaft pipe, which are of inch and are doubled, 
and the bilge-strake, which is 1 % inch thick for two-thirds the length amidships, 
gradually reduced forward and aft to {q inch. 
The bottom between bilge and garboard strakes is inch thick for three-fifths the 
length amidships, then gradually reduced to {g inch forward and aft. 
All butts of plating, keelsons, and stringers are double chain riveted, and the 
longitudinal seams lapped and single riveted. All plates are long enough to cover 
at least six frame spaces, except short plates at the ends; and there are at least 
two strakes between butts falling between same frames. All edges and butts are 
planed. 
Butts of garboard strakes are at least two frame spaces apart, as also are those 
of sheer strakes and deck stringers. All butts of plating are iirox)erly shifted. 
Bail: The rail is of white oak, 104 by 34 inches, let down to a fair bearing ou the 
bulwark angle-iron, hook-scarfed and edge-bolted through scaiTs. 
