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23. The areas of the water-line sections of a ship in square feet are 4,000; 3,200; 2,500; 1,500; 600; and 100 respectively; at distance between each of the sections is 2 feet. Find the dis ment of the ship in tons, neglecting the small appendage belc lowest water section.

24. Referring to the preceding question, find the number of tons must be taken out of the ship to lighten her 1 feet. Ex clearly the reason on which your work is based.

25. The area of the deck of a ship which is covered with plank is 4 square feet. Find the weight of the plank and its fastenings :(a.) If it is of Dantzic oak, 3" thick.

(b.) If it is of Dantzic fir, 34" thick.

(6

Second Stage or Advanced Examination.

INSTRUCTIONS.

Read the General Instructions at the head of the Elementary paper. You are only permitted to attempt twelve questions.

You must attempt No. 55. The remaining questions may be selecte from any part of the paper, provided that one or more be taken fro each branch of the profession, viz., Practical Shipbuilding, Laying Of and Calculations.

PRACTICAL SHIPBUILDING AND LAYING OFF.
Wood and Composite Ships.

31. What arrangements have to be made with respect to the form,
thickness, and texture of some of the blocks upon which a ship is
to be built?
(6.)
32. Give the names of the several timbers composing a common frame
or bend; and explain successively how they are situated with
regard to each other.
(6.)
33. What species of wood are used for the following timbers, and what
are the reasons for using such species? viz. :-keel, keelson, stem,
stern-posts, deadwood, knightheads, and frame timbers. (6.)
34. Explain fully in what ways iron riders give support to the frame
of a wood ship.
(6.)
35. Why is it necessary that the beams should have a round up?
What timbers take the place of the beams at the fore and after
extremities of a wood ship?
(6.)
36. Describe the methods of bending flat keel plates to form in a
composite ship. Explain how the iron is tested before it is used.
(6.)
37. What are the principal longitudinal ties in a composite ship?
Describe in detail how the several lengths of such ties are con-
nected together.
(8.)
38. Show how diagonal riders are fitted and secured in composite
merchant ships. Why are such riders fitted, and for what reasons
are they dispensed with in composite ships of the Royal Navy? (8.)

39. When two thicknesses of bottom planking are used in a composite ship, what precaution is necessary in working the scarphs of the inner thickness? (6.) 40. Give an account of the ordinary process of fairing the body, and also a brief description of the method of fairing by contraction. (8.) 41. The bevelling edges of the cant timbers being run off in the body plan, how are the bevellings taken from the floor and set off in the bevelling board? (6.) 42. The projection of a water-line not parallel to the keel being given in the body plan, how would you obtain the same in the half breadth and sheer plans?

(6.)

Iron Ships.

43. How are the dimensions of bottom plates ascertained before ordering them from the manufacturer? What margin in length and breadth is it usual to allow above the net dimensions? (6.) 44. What are the advantages and disadvantages of using short plates in the outer plating of a ship? (6.) 45. Show by a sketch and description how you would make a transverse bulkhead watertight where a longitudinal frame passes through it. (6.) 46. What are the uses of bilge keels? Show by sketches the various modes of forming and attaching them.

47. How are rivets and rivetted work tested?

(6.)

(6.)

48. State any instances of weakness of iron ships, caused by defects in their practical construction, that have been brought under your notice. (6.) 49. Explain the means that were adopted for remedying such weaknesses. What special injury is likely to result from the absence of an intercostal keel or keelson? (8.) 50. What points should be considered in arranging and determining the sizes of lightening holes in the longitudinal frames of a doublebottomed ship? (8.) 51. Give sketches of the fore and after parts of the half-breadth plan of any large iron ship, including the disposition of the frames. (8.) 52. Give a "correct" method of obtaining the round up of a beam mould. (6.) 53. What lines and sections appear on the sheer, half-breadth, and body plans respectively in their true forms? (6.) 54. How are the bevellings of the frame of an ordinary iron ship obtained, and how is the information communicated to the workmen? (6.)

Drawing.

55. Given the sheer plan of the stern of a screw steamer on a scale of -inch to a foot. Draw this to a scale of 1-inch to a foot, and show how the rudder should be hung, and explain the use of a dumb pintle.

(12.)

Calculations.

56. Find the area and transverse position of the centre of gravity of "half" a water-line plane; the ordinates in feet being 5, 6, 12, 16, 12, 10, and 5 respectively; the common interval being 15 feet. (6.) 57. Explain the method of obtaining the displacement of a ship by the double application of Simpson's rule. Show a convenient form of arranging the work of the calculation. (6.) 58. Define the "centre of buoyancy." A vessel is 180 feet long, and the transverse sections from the load water-line to the keel are semicircles. Find the longitudinal position of the centre of buoyancy, the "half" ordinates of the load water-plane being 1, 5, 13, 15, 14, 12, and 10 feet respectively. (8.)

59. Define the term "metacentre."

Write down and explain the formula, giving the height of the transverse metacentre above the centre of buoyancy.

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The "half" ordinates of the load water section of a vessel in feet are 5, 6, 9, 11, 12, 12, 12, 11, 10, 9, and 1 respectively, and the common interval is 12 feet, find the height of the transverse metacentre above the centre of buoyancy, the displacement of the vessel being 420 tons.

(8.) 60. Referring to the preceding question, find the transverse inclination of the vessel from the vertical if a weight of 8 tons, already on board, be moved from one side of her to the other through a distance of 12 feet; the centre of gravity of the vessel being 3 feet above the centre of buoyancy.

tan 3°
tan 4°

0524

0699

[blocks in formation]

61. A watertight bulkhead formed of iron plates" thick, lap-jointed, lap-butted, single riveted, is stiffened by angle irons 3"x3"x7" placed vertically 30 inches apart. Find the weight of 100 square feet of the bulkhead.

(8.)

62. Sketch a well-arranged disposition of butts and edges of bottom plates with their fastenings. Give the dimensions of plates; diameter and pitches of rivets in frames, butts, and edges. Sketch the probable lines of fracture if the vessel were unduly strained, and show by calculation that the system you give is a well-arranged (10.)

one.

Honours Examination.

INSTRUCTIONS.

Read the General Instructions at the head of the Elementary paper.

You are only permitted to attempt fourteen questions. You may select these from any part of the paper, provided that one or more be taken from each branch of the profession, viz., Practical Shipbuilding, Laying Off, and Calculations.

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