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Junior Examination Papers, 1894 . 
10. Given that the temperature of the atmosphere varies from 55° to 65° 
Fah., give approximately the corresponding temperatures at intermediate 
degrees suitable for churning ripe cream. Would you make any difference in 
the case of sweet cream and of whole milk ? 
EXAMINATION IN ELEMENTARY CHEMISTRY. 
Maximum Number of Marks, 200. Pass Number, 75. 
Tuesday, November 13, 1894. 
( Three hours allowed.') 
1. What is, speaking generally, the chemical composition of the atmosphere, 
and which are the constituents found in it that take part in the processes of 
vegetation ? 
2. Mention the principal uses to which oil of vitriol is put in agriculture. 
3. Which are the chief gases composing coal gas ? Name their leading 
properties. Which are the common impurities of coal gas ? 
4. What is alumina ? Mention its use in the Arts. 
5. Describe the properties and uses of wood charcoal and animal charcoal. 
How would you distinguish them from one another? 
6. In what form is lead chiefly found in nature ? How is the metal prepared 
from its ore ? 
7. How many different sets of compounds does copper form ? How could 
the presence of a copper salt in a solution be detected ? 
EXAMINATION IN MECHANICS AND NATURAL PHILOSOPHY. 
Maximum Number of Marks, 200. Pass Number, 75. 
Wednesday, November 14, 1894. 
( Three hours allowed.) 
1. What is the centre of gravity of a body? Mention one property of the 
centre of gravity. If a body were hung up by a piece of string fastened to 
point of it, in what position would it come to rest ? 
2. Draw a triangle ABC, with C vertically over A, and make AC two and a 
half inches long ; take o the middle point of bc. Let ab represent a uniform 
rod, weighing 20 lb., which can turn freely round a hinge at A, and is supported 
by a string fastened to b and to a fixed point at c ; show that Aoc is a triangle 
for the forces that keep ab at rest ; and find from it the tension of the string, 
and the pressure on the hinge. 
3. Define a lever and its fulcrum. Give an example of a lever. 
What relation holds good between the power and weight in a lever ? 
There is a lever 10 ft. long with a fulcrum at one end ; if it be required to 
support a weight of one ton by a force equal to 70 lb. weight acting at the 
other end of the lever, at what point of the lever must the weight of one ton 
be applied ? 
4. A body whose weight is 50 lb. is just drawn along a horizontal plane by 
a force acting horizontally and equal to 7 5 lb. weight ; what is the coefficient 
of friction between the body and the plane ? 
Define the coefficient of friction and state the laws of friction. 
5. Define a foot pound of work. 
If the ton weight in question 3 were raised a quarter of an inch, how many 
foot pounds of work must be done by the force of 70 lb., and through what 
distance must the point of application of that force bc moved ? 
6. Write down a formula for finding the distance through which a body 
would fall freely in a given time, and state in words the meaning of the for- 
mula. 
If a body fell freely from rest through 90 ft. in a certain time, through 
what distance would it fall from rest in a third part of that time ? 
7. State how to find the specific gravity of a body by the balance. 
