Faraday, the great electrician, was not satisfied to read of new experiments, but made a practice of working them out for himself, that he might observe everything connected with the processes, and learn from personal observation the pftenonena peculiar thereto. The example of this illustratrious man can well be followed, as far as possible, by all who desire to study Electricity and Magnetism, and it will be the purpose of these chapters to so present the subjects by means of simple and characteristic experiments, that anyone may acquire an elementary knowledge which will serve as an excellent foundation for more advanced work.

With this brief statement of our aims, we will consider the subject of Magnets. This name is applied to any body which has the property of attracting iron. In the natural form it was known to the ancients, being found at Magnesia, in Asia Minor, hence the name. It is also found in Spain, Sweeden, Arkansas and other parts of the world. In its natural state it is a heavy dark brown or black stone. Its property of attracting iron is best studied by bringing it in contact with iron filings, and this will be our first experimmt. Experiment 1. Procure a small quantity of clean iron filings from a machine shop, or make them by filing a piece of cast iron with a coarse file. Lay a piece of Magnetite, (magnetic oxide of iron) upon the filings, turning it over so that all sides and the ends will come in contact with the filings. Upon lifting, we observe that the filings are so strongly attracted at the end, that a considerable quantity is retained thereon, but that at the centre no such attractive force seems to exist.

There is another property peculiarity to this stone, which was discovered by the Chinese; if suspended by a string it will turn so as to point north and south hence the name Lodestone, or leading stone. In the navigation of ships this was the compass of earlier days. Experiment 2. Suspend a piece of Lodestone by a strand of untwisted silk and observe the tendency to turn as stated, The natural magnet possesses the property of imparting magnetism to pieces of hard iron (steel,) making of them artificial magnets.

Experiment 3. Take a piece of steel (large sewing needle or knitting needle) and rub one end from the centre with one end of piece of Lodestone; rub the other end from the centre with the other end of the ore. See if the piece of steel will attract iron filings, and at what points the attractive force is greatest. Suspend at the centre with stirrups made of small copper wire and held by a strand of untwisted silk thread, and see if it will turn and point north and south.

This artificial magnet is a simple form of the mariner's compass, the latter being more strongly magnetized, and suspended in a more sensitive and usable way. The ends of a magnet, (either natural or artificial) are called the Poles; that pointing towards the North being generally termed the North pole, and the other the South pole. All magnets will have both poles in some form, the attractive force of the earth acting upon each, being about equal. The reason why the magnet points North and South is that the earth is a great magnet with magnetic poles, which are not the same, however, as the geographical poles. Why the suspended magnet turned* will now be learned in Experiment 4. Suspend the bar magnet as in the brevious experiment, and note the North seeking end or pole. Holding in the hand a similar bar or horseshoe magnet, bring the N pole, which has been marked to indicate it, near the N pole of the suspended magnet. The N pole of the latter is repelled by the N pole of the magnet held in the hand; if the other or S pole is held near the N pole of the suspended magnet the two are attracted towards each other. After trying each pole of each magnet, we will learn that; - Like poles repel, and unlikepoles attract each other. From this we learn that there must be two kinds of magnetism; that which is attracted towards the N magnetic and that which is attracted towards the S magnetic pole. From what we have already learned of the attractive and repelling force of like and unlike poles, it follows that the magnetism of the earth's poles must be of the opposite kind to those of the magnets. The magnetism of the earth's N pole must be S magnetism, the N magnetism being at the South magnetic pole.

It has been already stated that, with the bar magnets used in the preceediug experiments, the earth's magnetic force affected the poles of the magnet equally. The following experiment will show that this is true. Experiment 5.

Magnetize a large sewing needle. Place same on a piece of thin cork, along the top of which has been cut a groove for holding the needle in position. Place in the centre of a shallow dish of water. If the needle has been sufficiently magnetized, it will slowly turn and point North and South, but with no tendency to move towards either of these points.

As permanent bar magnets will be necessary to other experiments to follow, the following directions for making a pair are given at this time, that they may be used in experiments. The principles governing the method used will be considered at another time.

Obtain two pieces of tool steel, 4" long, $" wide and i" thick, and smooth all sides and ends with a fine file and emery cloth; wind one the full length with a close coil of magnet wire, about No. 16 guage. Connect the ends of the wire coil with a battery of several dry cells connected in multiple, i. e., the carbon or centre terminals connected to one wire, and the zinc or outer terminals to another wire. Take careful note of which way of the piece of steel is contained in the coil, the way the coil turns around the steel, and the ends of the coil connected to the carbon and zinc terminals of the battery. Allow the current to flow around the coil for a few minutes, lightly tapping the end of the steel with a small hammer. Remove the piece of steel and it will be found strongly magnetized. Test with a suspended bar magnet to determine the polarity of the ends, marking the N pole with a slight scratch across one side near the end. Mark the other piece of steel with a similiar scratch, place in the coil and magnetize so as to have that end the N pole. Reversing the connections with the battery, or the direction of the winding of coil around the piece of steel will reverse the polarity of the magnet.

For storing bar magnets when not in use, make a block of wood long and wide enough to have a dividing strip of wood 1/2" wide between the magnets, and at each end a " keeper " made of soft iron. These should always be placed against the poles of the magnets, and will prevent them from loosing the magnetism.