Has, however, suffered many changes during our visit. The heart-breaking part of human hands. A.W. UPLANDS, STOKE POGES, BUCKS. CONTENTS. Chapter I.--THE STEAM-ENGINE. What is electricity?--Forms of electricity--Magnetism--The permanent magnet--Lines of force--Electro-magnets--The electric bell--The induction coil--The condenser--Transformation of current--Uses of the dark rays of the flume.