distribution of free magnetism along a bar magnet, and
of the lines of force due to a bar magnet, to a horse-shoe
magnet without and with its keeper, to various groups
of bar magnets, and to pieces of soft iron in the field of
a strong magnet ; law of oscillations ; use of the method
of oscillations in comparing the force of the earth's
magnetism at a place with that of a magnet at the same
place, in comparing the strength of two magnets, and in
examining the surface distribution along a bar magnet.
Terrestrial magnetism ; declination and mariner's com-
pass ; inclination and the dip-needle ; determination of
the magnetic meridian, and of the dip at a place ; the
magnetic elements of a place ; comparison of horizontal
forces at different places ; the explanation of the be-
haviour of a compass-needle and of a dip-needle at
various places on the earth's surface ; magnetization of
a steel bar under the influence of the earth's magnetism.
Statical Electricity : Two kinds of electrification,
their simultaneous and equal development, and their
mutual reactions ; conductors and non-conductors ;
electrification by contact ; influence of a charged body
on earth-connected and on insulated bodies ; “free ”
and “ bound” electricity. Gold-leaf electroscope ; the
electrification of it by contact and by influence ; the
interpretation of its indications ; the use of it in examin-
ing the seat and distribution of charges on solid and on
hollow conductors of various shapes. The electrophorus
and frictional electrical machines ; the action of sharp
points. Laws of electric action ; electrostatic units ;
capacity ; potential ; the relation between the quantity
of electricity and the capacity and potential of a charged
sphere ; surface density ; energy of discharge ; the use
of the electroscope in examining the effects of alteration
of the area of a charged body on the density of its charge,
the disturbance of the distribution of the charge on a
body produced by the presence of another charged body,
and the electrical condition of a hollow conductor
enclosing a charged insulated body ; electric screens ;
subdivision and redistribution of charges on spheres of
equal and of different radii after contact. The Leyden
jar; conditions on which its capacity depends ; its
charge and discharge ; the seat of the charge. Description
and construction and principles involved in the use
of electrostatic induction machines, condensers, and the
quadrant electrometer.
Current Electricity : The parts of a simple voltaic
cell and chemical action within it ; polarisation, its cause
and effects ; the chief kinds of voltaic cell ; conditions
which a good cell should fulfil ; Ohm's law, and simple
applications of it ; absolute and practical units ; the
total and the available electro-motive force in a circuit ;
combinations of cells to form batteries ; magnetic effect
of the current. Magnetic properties of a coiled con-
ductor ; Maxwell's rule ; De la Rive's floating battery.
The mutual action of currents upon one another and the
interaction of currents and magnets. The magnetic
circuit ; reluctance ; electro-magnets ; graphic representation
of lines of force due to a solenoid and to an
electro-magnet. Conductance and resistance of wires ;
resistance of conductors in series and in parallel ; shunts.
Methods for the measurement of the strength of currents,
electro-motive forces, resistances, and power. Principles
on which these methods depend ; construction and use of
instruments required for their practical application.
Development and distribution of heat in a circuit ; Joule's
law ; electric lamps ; thermo-electricity. Chemical effect
of the current ; electrolysis of water, of hydrochloric acid,
of sulphate of copper, and nitrate of silver ; voltmeters
and the use of them ; electric energy and power ; available
and wasted power. Induction of currents. General
principles of the construction and description of simple
forms of continuous-current dynamos and motors.