MENSURATION	357
14. The barrel of a wire reel is 3 feet in diameter and 3J feet long.
Find (a) how many turns of a 3-inch wire will go on the drum to complete
a single layer, (b) what length of wire will be in the layer?
15 The paddle wheels of a steamer are 21 feet in diameter and make
2000 revolutions. How many nautical miles did the ship go, neglecting
slip?
16. The outer and inner radii of a hollow spherical shell are 8 inches
and 7 inches respectively. Find the volume of the shell.
17. The diameter of a cylinder is 14 inches.   What length of steel
bar is required to form a ring to fit inside of it?
 18.	A ship in rounding a point maintains a constant distance of
3 miles from it whilst the bearing of the point alters 65°.   What distance
in miles did she sail?
 19.	There are 20 turns of wire on the barrel of a winch the diameter
of which is 28 inches.   Find the length of the wire in feet.
 20.	A ship on steaming trials is turning in a circle on port helm.
She takes 6£ minutes steaming at 5 knots to complete the circle.   Find
(a) the distance travelled by the ship; (6) the diameter of her turning
circle.
2L A barrel 3 feet long, bilge diameter 24 inches, end diameter
18 inches, weight of barrel 35 Ibs. Bequired its reserve of buoyancy
in salt water.
 22.	Eggs and butter are to be stowed in a cold storage chamber
measuring 15 ft. X 20 ft. X 25 ft., the eggs in crates stowing at 100
cubic feet per ton and the kegs of butter at 60 cubic feet per ton.   If
the combined weight of the eggs and butter is 90 tons, required the
maximum quantity of each that can be put into the chamber.
 23.	A marine boiler is 16 ft. I| ins. internal diam. X 12 ft. 6 ins.
long.   The furnaces, tubes, etc., occupy 26 per cent, of the volume and
the steam space 30 per cent, of the volume, calculate how many tons
of fresh water the boiler requires to fill it to the working level, and how
long will it take to fill the boiler to this level if the pipe delivers 150
gallons per minute.
 24.	The pontoon of a floating dock is 560 feet long, 100 feet beam,
and the draft in S.W. with a ship in the dock is 14 ft. 6 ins. there being 600
tons of water in the tanks of the dock.   If the weight of the dock with
complete equipment and tanks empty is 12,050 tons, find the weight of
the ship.