Apply the result to find an expression for the magnetic force and magnetic induction in an iron anchor ring wound with a conducting circuit carrying a current (a) when the ring is continuous, (b) when it contains an air gap.

11. Shew that the capacity of a condenser expressed in electrostatic units is v2 times its value in electromagnetic units, where v is the ratio of the electromagnetic unit of electricity to the electrostatic.

A condenser of 1 microfarad is made up with its dielectric of average thickness 0.01 cm.; find the area of the sheet of dielectric of that thickness which would be required for the construction of the condenser. (1 microfarad = 10-15 electromagnetic units of capacity; v = 3 × 1010.)

12. Explain why a difference of phase is established between e.mn.f. and current in an alternator.

Express this difference of phase in terms of resistance, inductance, and rate of alternation.

NATURAL PHILOSOPHY.-PART III.

PRACTICAL EXAMINATION.

The Board of Examiners.

1. Determine and tabulate the pressure corrections of the given aneroid.

2. Adjust the given galvanometer for maximum sensitiveness; and determine the strength of the current which will give a deflection of 1 scale division.

8. Determine the constant of a capillary electrometer. 4. Determine the specific resistance of the given liquid.

5. Verify the formula connecting the resolving power and breadth of a narrow rectangular object glass.

6. Determine the polarising angle for the given glass plate; and deduce its refractive index.

ASTRONOMY.

The Board of Examiners.

1. Describe the construction and mode of adjustment of the Transit Circle.

2. Give a full account of the two principal observatory methods of finding the latitude, and shew that the advantages and defects of the two methods are largely complementary.

3. Discuss the principal circumstances which give rise to the Equation of Time, and describe the general course of the variations of this quantity. 4. Explain what is meant by "Nutation," and point out the origin of the various nutational terms employed in the reduction of observations.

5. Discuss the nature of the initial surface stresses developed in a spherical mass of homogeneous liquid suddenly set in rotation, and express their magnitude as a function of the latitude.

Apply your result to give a general explanation of the actual forms of the planets.

6. Give a full account of the investigations by which the distance of any one fixed star has been determined.

CHEMISTRY.-PART I.

Professor Masson.

PASS AND FIRST HONOUR PAPER.

N.B.-Verbal descriptions of chemical processes should be supplemented as far as possible by formulæ and equations.

1. Give the equation for the action of ammonia on nitric acid; and calculate from it the weight of ammonia contained in one litre of a solution of which 10 cubic centimetres are exactly neutralized by 7.5 c.c. of a solution containing 21 grammes of nitric acid per litre.

2. Describe methods generally available in the laboratory for the preparation of the following in the pure state, and give one special case to exemplify each :—

(a) The hydroxide of a heavy metal from a soluble salt of the same;

(b)

(c)

The oxide of a metal from its sulphide;
A volatile acid from one of its salts;

(d) A soluble salt of a metal from its carbonate; (e) A reducible metal from one of its salts.

3. Describe, explain, and formulate the actions which occur when hydrogen sulphide in aqueous solution is destroyed by (a) exposure to air, (b) nitric acid, (c) ferric chloride, (d) acidified solution of potassium bichromate, (e) acidified solution of potassium permanganate.

4. Give such an account of "the alkali metals " as will explain (without reference to the Periodic Law) the view that they form by themselves a natural group of elements.

5. Give an account of phosphoric acid and its more important salts.

6. Explain what is meant by primary and secondary products of electrolysis, and give examples.

CHEMISTRY.-PARTS II. AND III.

Professor Masson.

PASS AND FIRST HONOUR PAPER.

1. Discuss the attempts to extend Dulong and Petit's law of atomic heats to elements in combination.

2. Explain and exemplify the indirect determination of the heat of formation of a compound.

3. Explain the following statement:-The physical properties of dilute solutions are colligative, and

may, therefore, be utilized for the comparison of molecular weights.

4. Explain what is meant by the coefficient of ionization of a salt in aqueous solution, and show how its magnitude is estimated from conductivity data.

5. State the law of mass action, and show that it is compatible with the law of definite proportions. Show the working of the law by reference to a few actual cases, selecting such actions (a) become complete, (b) lead to equilibrium.

6. Discuss the valence of the nitrogen atom.

as

TECHNICAL CHEMISTRY.

Professor Masson.

Give accounts of the following:-
:-

(1) The ammonia soda process.

(2) The metallurgy of aluminium.

(3) The manufacture and technical uses of the salts of manganic and permanganic acids.

(4) Modern improvements in gas lighting.

(5) Smokeless powders.

(6) Anthracene dyes.