Ixxxii Agricultural Education — Examination Papers, 1882. 
30 lbs., what force is exerted on the nail ? Why would the force on 
the nail become less as it rises out of the wood ? 
3. What is the centre of gravity of a body, and what is its cha- 
racteristic property ? Where is the centre of gravity of a sq[uare 
lamina, of a circular lamina, and of a triangular lamina ? 
Draw a square ABCD, and on AB draw an equilateral triangle 
ABP, the point P falling within the square ; if ABCD is a rigid 
lamina weighing 20 lbs. and resting horizontally on three points 
under A, B, P respectively; find the pressure on each point. 
4. What is meant by the work of a force ? What is a foot-pound 
of work ? 
A rectangular block weighing 27,000 lbs. is 2 yards high, and its 
base is a square the length of an edge of which is a yard. If it 
stands on its square base how many foot-pounds of work are required 
to overthrow it? If it lies on one of its long faces how many 
foot-jjounds of work are required to make it stand up on its base ? 
N.B.— I.e., the square root of 6 = 2-23607. 
5. What is the numerical measure of the kinetic energy of, or 
work accumulated in, a moving particle ? 
The mass of a particle moving at the rate of 24 feet a second is 
10 lbs. ; how many foot-pounds of work is it capable of doing in 
virtue of its kinetic energy? Find the constant force by which the 
particle would be brought to rest after moving through 8 feet. 
6. Exjilain the principle of the hydraulic press. What practical 
difficulty long stood in the way of its application ? Explain the 
contrivance by which the difficulty was overcome and a working 
hydraulic press constructed. 
7. Explain the action of the common force pump, and the use of 
the air-chamber with which force-pumps are sometimes fitted. 
8. If a lump of ice is taken at 0° F. and heat is applied to it, what 
arc the successive changes it undergoes, (a) in volume, (6) in tem- 
perature, until it is all boiled away ? It is sui)posed to be in free 
■contact with the air throughout the whole process. 
9. A piston 1200 square inches in area is moved forward by a 
varying i)ressure througli a distance of 6 feet ; the pressure in pounds 
per square inch at each foot of the stroke is 18, 18, 18, 12, 9, 7, G ; 
calculate the foot-pounds of work done by the pressure in one stroke, 
and draw the indicator-diagram corresponding to these forces. (The 
vacuum ^Ji'cssure is to be neglected.) 
EXAMINATION IN MENSUKATION AND SURVEYING. 
Maximum Number of Marks, 100. Pass Number, 50. 
Thursday, Mai/ 11th, from 2 p.m. till 5 p.m. 
1. State the rules for finding the area of a triangle in terms of its 
.sides, the area of a circle, and t]io volume of a cylinder. 
The sides of a triangle arc 110 feet, 130 feet, and 160 feet 
