Q. 62. A retaining wall with vertical back and battering face is 12 feet. high above lower ground level, 1 foot thick at top, and 3 feet thick at bottom; it supports safely a bank of earth level with the top having a natural slope of 45 degrees. Draw the wall to a scale of("to a foot) and show the line of thrust when the wall weighs 1 cwt. per cubic foot, and the earth 90 lbs. per cubic foot, and calculate the stress on outer edge of base assuming that the wall has no tensile strength. What thickness must a rectangular wall of the same material be to do the same work with the same maximum stress?

Although attempted by 79 candidates this question was, as a rule, very badly answered, few knowing even how to find the thrust against the wall, although there were one or two good answers. Eight obtained no marks, while none obtained full marks. Some misread the question, taking the "bank of earth level with the top" to imply a surcharged wall, but these knew still less how to find the thrust. Several gave the thrust of the earth as acting through the line joining the centres of gravity of the earth and the wall, and there is no doubt that the teaching was in fault in this respect. Other whole classes gave the horizontal thrust equal to the weight of the earth wedge. The maximum pressure was frequently given in lbs. per square inch, but the common custom is to give the pressure on building materials and foundations in tons per square foot. The equivalent rectangular wall was in the majority of answers given as equal to the mean thickness of the battered wall.

Q. *63. The diagram shows the plan of a roof covered with slates with lead hips and valleys and ornamental tile ridging. Write a specification for (1) the joiner's work for one of the dormers; (2) the slating; and (3) the plumber's work.

This was attempted by 143 candidates, only one of whom failed to get any marks. Many candidates gave a good specification for one of the trades, but very few were equally good in all three trades. Specifications should always be definite, such expressions as "if required," "if necessary," etc., applied to ordinary details of construction show a doubt amounting to ignorance of how the work should be constructed.

Q. 64. Draw to a scale of (8 ft. to an inch) plan of a class room for 40 infants in an elementary school, showing the entrance door, the windows and the seats; also a cross section passing through one of the windows; also draw to a scale of (" to a foot) cross section through the seats. No fireplace need be shown.

This was attempted by 153 candidates, all but one obtaining some marks. There were many good answers so far as the planning and the section were concerned, but some gross mistakes in the cross section through the seats. A common height given for the infants' seats was 1 foot 5 inches, one gave 2 feet. One gave the room as 40 feet by 34 feet 9 inches, by 20 feet high to flat ceiling, arm-chair seats 2 feet wide and 15 inches deep, single desks, with flat top, 2 feet 6 inches by 2 feet. Several got over the difficulty of knowing which side the windows should be by putting them on all four sides.

Q. 65. Describe the construction, mode of driving, and advantages of concrete piles.

Attempted by 125 candidates, three of whom obtained no marks and one full marks. There were a few good answers to this question, but the sketching was, as a rule, very poor. The majority of the descriptions were very vague, particularly with regard to the driving of the piles. So many candidates stated that the piles should be driven by forcing a jet of water down a pipe through the centre, instead of mentioning this as a special case; that there has evidently been imperfect teaching. One said a groove was made down the side of the pile to pass a hose down. Nearly all stated that the driving was done by a monkey, whereas the monkey is the clip hook that runs up and down to raise and release the ram, hammer, or tup that drives the pile. One wrote "the piles are usually driven in with what

is called a monkey, which is a huge hammer driven by hydraulic means." Many said concrete piles were formed by steel cylinders sunk in the ground, the core dug out, the concrete filled in and the steel cylinders withdrawn after the concrete had set hard. This again shows either defective teaching or a collective misunderstanding of the "Simplex" and allied systems.

Q. 66. A factory chimney shaft, octagonal on plan, and having an internal diameter of 6 feet, is to be erected 80 feet high above top of footings. Draw to a scale of 8 feet to an inch a section of one wall from top to bottom showing the cap and the footings, and a plan of the shaft taken at a height of 30 feet from top of footings. Also, draw to a scale of " to a foot an enlarged section of one wall for a height of 15 feet above the footings showing the firebrick lining, and state how high you would carry this.

Attempted by 113 candidates, of whom four obtained no marks. There were many bad failures in the answers to this question. The majority of those attempting it knew that the set-offs occurred at intervals of 20 feet, but they did not know that over 5 feet diameter the top length should be 14 bricks thick. The common errors were to bond the fire-brick lining to the main wall, to project the concrete inside the base only to the same extent as on the outside instead of right across, and to put air inlets to the space between the chimney wall and lining, which only tends to spoil the draught.

Q. 67. The diagram shows the party-wall between two houses without

basements in a terrace of uniform height. One house is to be pulled down and in its place a hotel is to be erected with a basement 12 foot below the original ground-floor level, and the party wall is to be carried up 20 feet above its original height. It is decided not to pull down the old wall but to underpin and thicken it. Draw to a scale of 4 feet to an inch a section from top to bottom of the wall when raised and thickened, including footings, hatching in the old portion, and figuring the total thickness at the various stages. Describe fully the precautions which you would take while doing the under-pinning.

This was the most popular question, being attempted by 155, but the same ignorance of practical work in underpinning was shown in these answers as to Question 49 in Stage 3. Needles through a wall to be underpinned are exceptional, and adjoining property should be interfered with as little as possible. Comparatively few mentioned the bonding of the new portion to the old in the thickened walls, or the erection of flying shores across the site between the existing buildings. Many carried up the new work flush with the old 14 inch wall on the further side, and so encroached 24 inches on the existing roofs. A large number left in the whole of the footings and concrete, building round them on the inside. The majority of those who mentioned shoring described raking shores on the hotel site and many said they were to be left in until the thickening was completed.

Q. 68. Describe with sketches, the lighting, ventilating and heating of a ward containing 6 beds in a cottage hospital.

Attempted by 87 candidates of whom only one failed to get any marks. Some of the answers to this question showed a practical acquaintance with the subject, and very good plans were given, others showed no knowledge of the ordinary requirements and gave also very rough sketches. Neat sketching is most important.

Q. 69. Show by diagrammatic sketches what difference is produced in the bending moments of a beam continuous over three equal spans (a) when the three spans are uniformly loaded; (b) when one of the end spans is unloaded; and (c) when both the end spans are unloaded.

This was attempted by only 36 candidates, of whom 11 obtained no marks at all. The majority of the answers showed no knowledge whatever

of the stresses on continuous beams, and only one candidate was approximately correct. The majority of the sketches were exceedingly rough. Very few candidates seemed to know that there was any difference between bending and bending moments.

Q. 70. What is meant by the term "modulus of elasticity"? Assuming the modulus of elasticity of wrought iron to be 26,000,000 lbs. per square inch, calculate the length of a tie-bar, 2 inch diameter, when loaded tensionally with 30 tons, if its length when unloaded was 20 feet.

Attempted by 49 candidates, of whom five obtained full marks and four none. Many of the answers were distinctly good and, on the whole, the question was fairly well answered by those who attempted it. Some of the answers were spoilt by such fractions as 20 8888 feet, 20 feet, 20 feet and 4800, of an inch, instead of 20 ̊0164 feet, or 20 feet 0197 inches. Several gave the modulus of elasticity as the force that would double the length of a bar if its cross section remained unaltered, and several others stated that it was the force that would stretch a bar to double its length or compress it to half its lengih. This shows very defective teaching.

HONOURS PRACTICAL EXAMINATION.

Seventy-three candidates, from among those who sat for the Honours paper this year, were admitted to the Practical Examination in Design, the subject being a lodge and entrance gates for a park. As far as the drawing is concerned, a considerable improvement was shewn as compared with the work sent in last year, and the majority of the elevations were good, but the planning was in many cases very defective. The main faults were: (1) Want of compactness and a failure to appreciate clearly how the building would be roofed. This should always be kept distinctly before the mind of a designer when making the plan of a building. (2) Awkward arrangement of the staircases. Not only were these often shown in a bad position, but they were in many cases far too steep, and insufficient horizontal space was allowed to work in the stairs properly. (3) Bad arrangement of fireplaces. Those on the upper floor were often placed without any reference to those on the ground floor, and in positions where it would be impossible to carry the jambs without elaborate constructive expedients the necessity for which was evidently quite unappreciated. Several designs were really excellent, and showed much taste, but many candidates had too evidently taken the speculating builder's suburban villa as their model. The entrance gates and piers were on the whole satisfactory, and some of the window details were very good. In too many cases the estimate of cost was too low, and the price put down for the gates and piers was occasionally ludicrous.

Report on the Examination in Naval Architecture.

The number of candidates in Stage 1 was 22 less, and in Stage 2 the same as sat at last year's examination. On the whole there was an improvement in the work sent in as compared with last year. A number of candidates answered more than the number of questions permitted, and there was a comparatively large number of failures due to candidates not answering the compulsory questions, or not selecting questions from each of the sections into which the examination paper is divided. It therefore appears that the instructions printed at the head of the examination questions are not sufficiently read, or that the importance of carrying out those instructions is not sufficiently realised. Arithmetical errors were far too common in both stages, and the work should be done with more system.

The rough sketches in connection with the practical questions were well done on the whole. Some of these sketches were exceptionally good, but

generally in such cases the number of questions answered was comparatively few, and there may have been some cases where, on account of spending too much time on well-finished sketches, by the use of instruments (a test of which is given by the drawings required to be done to scale), a sufficient time has not remained for those students to attempt the number of questions permitted, and possibly obtain a higher class. What is required in answering the practical questions is clear freehand sketches, approximately to scale, and these should be encouraged. In Stage 2, 39 candidates failed through not answering any of the questions set in the "Laying Off" section of the paper. This is an important branch of the subject, and it should receive more consideration than the results of the examination seem to indicate it has received. Teachers should bring the above points strongly before the notice of the students.

STAGE 1.

Results 1st Class, 134; 2nd Class, 119; Failed, 78; Total, 331.
PRACTICAL SHIPBUILDING.

Q. 1. Show by sketches, the forms of sections of rolled steel bars commonly used in shipbuilding; name them, and state for what parts of the vessel they are severally employed.

A favourite question, attempted by about 81 per cent. of the candidates, and the answers were generally very satisfactory.

Q. 2. Sketch a set of building blocks, and show how they are secured in place. What is the spacing and dimensions of the blocks your sketch represents?

Attempted by about 55 per cent. of the candidates, and the answers were generally satisfactory; but some of the candidates did not show very clearly how the blocks are secured in place, and others gave sketches of blocks used for "dry-docking," instead of those used on the building slip.

Q. 3. Sketch roughly a stern-frame for a single screw-vessel, showing how it is secured to the keel and shell plating. Of what material is the stern post made?

Attempted by about 53 per cent. of the candidates. Many of the sketches. were very good. A few candidates stated that "cast-iron was the material the stern post was made of; this should have been "cast-steel," but frequently forged mild steel is used.

Q. 4. What is a deck stringer plate? What are its uses? Show by a transverse sectional sketch how you would connect a deck stringer to the beams, framing and shell plating of a ship. Attempted by about 42 per cent of the candidates. Generally satisfactory, although a number of candidates did not shew the rivets connecting the stringer to the beams and side plating, or did not state the uses of the stringer clearly.

Q. 5. Make a rough sketch showing the cross section of a side-bar keel, and its connections to the garboards and transverse frames. How are the butts of the keel disposed?

Attempted by about 46 per cent. of the candidates, and the answers were generally satisfactory, except that the disposition of the butts of the keel were frequently omitted; many of the sketches were very good. A few candidates sketched the bar and flat keel plate instead of the side-bar keel. Q. 6. Sketch and describe the different kinds of fixed pillars used in shipbuilding. Where are they fitted? What purposes do they serve, and how should they be arranged for maximum efficiency? Attempted by about 36 per cent. of the candidates, and, with a few exceptions, was fairly well answered. A number of candidates described and sketched a portable pillar," but this was not asked for in the question, "fixed pillars" only being referred to.

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Q. 7. Describe the method adopted in the shipyard for bending a beam to its correct curvature. Show by sketches and otherwise how the beam arms are formed in the case of (1) a bracket plate knee, and (2) a slabbed or welded knee. What is the depth of the beam knees?

Attempted by about 37 per cent. of the candidates, and the answers were generally very satisfactory.

Q. 8. Show by sketches the disposition of the rivets in (1) a double riveted lapped joint, and (2) a treble-riveted butt joint. State the distances of the rivets from the edges of the plates and from each other, in terms of their diameters, supposing the joints are to be made watertight.

Attempted by about 53 per cent. of the candidates, and the answers as to the disposition of the rivets were generally satisfactory; but in some cases the spacing of the rivets was not stated clearly, whether it was intended from edge to edge, or centre to centre of the rivet holes. Some of the candidates shewed a disposition of rivets suitable for "non-watertight" work. Q. 9. What is a side keelson? Sketch one, showing its connection to the other parts of the vessel, and state what useful purpose it

serves.

Attempted by about 28 per cent. of the candidates, and the answers were generally poor and incomplete. The useful purposes served by such keelsons were frequently not stated. A few candidates gave sketches of side stringers or bilge keels.

Q. 10. Describe by sketches and otherwise, how a large transverse water tight bulkhead is constructed and secured to the ship.

Attempted by 26 per cent. of the candidates; about one-half of the answers were satisfactory, the sketches of the remainder were poor and incomplete.

DRAWING.

Q. 11. Enlarge, in pencil, the given drawing, to a scale of twice that upon which it is drawn.

Only three candidates failed to attempt this question, which was generally well answered. Some candidates traced the sketch on the tracing paper attached to the examination sheets and then placed working lines on the tracing. There is no need for this, and the working lines should be placed on the sketch sheet supplied.

CALCULATIONS.

Q. 12. What are the weights of a cubic foot of wrought iron, mild steel, yellow metal or gun-me tal, teak, English elm, and yellow pine?"

A mild steel plate 10" thick is 18' long, 5' wide at one end, tapering to 3' 6" wide at the other end, and has two circular lightening holes cut in it 2 and 1' 6" in diameter respectively. What is its weight in lbs?

Attempted by about 52 per cent. of the candidates, and the answers to the first part of the question were very satisfactory, but some of the answers to the second part were full of arithmetical errors, and shew a want of system in setting out the work clearly. There was frequently a mixing up of units, and multiplying feet by inches.

Q. 13. What is meant by "displacement" and "centre of buoyancy"?

The water-planes of a vessel floating in sea water are 3' 6" apart, and their areas, commencing with the load water-plane, are:13540, 11755, 8520, 3875, and 0 square feet respectively. Calculate the displacement of the vessel in tons.