Now let us discuss how to measure the H. I mean the horizontal component of the words magnetic field using the tangent galvanism. So tangent galvanism determination of the horizontal component of the words magnetic field. The apparatus required that is all. The tangent galvanism is a tangent galvanism term. The battery, the elementation which provides a voltage, a combinator or a reversing key. This has got four terminals going to the tail and along there. A variable resistance goes by the ring Rio starch and I am meter to measure the current and then few connecting wires. The slightly connected is given as follows. The positive terminal to the battery is being connected to the combinator and the opposite end of that is given connection to the positive of the ammeter. Come the negative and the terminal meter the wire goes to the top end of the Rio starch and for the bottom end of the Rio starch the wire goes to the negative terminal of the battery. The remaining two terminals of the combinator are attached parallel to the tangent galvanism in which we are using two turns of wires, two turns of wires. So if the number of wires number of turns is less, correspondingly the current that has to be supplied is greater. After giving connection to the audience with two important precautions or initial solutions, the sharps are up. See the ammeter that is a magnet today which is one we place anywhere close to the TV tangent galvanism. The tangent galvanism essentially carries a small magnetic needle with which only we measure the different angles. So this magnet will be affected by the magnet that is present in the ammeter because there should be placed wide apart from each other. The next report we will see set up is that the coil of the tangent galvanism is this is the coil through which the current will flow should be placed parallel to the magnetic needle which you can see as a black small diamond kind of diamond needle. So I have to place it parallel to that. So the coil is placed parallel to the magnetic needle. This is called magnetic meridian. After that you can see a thin pointer here that should be made to coincide with 0 0 position 0 as you can see here 0 of the compass box in the tangent galvanism. So the pointer coincides with 0 of the tangent galvanism. Now, connections are given to the mains. So, the magnet is also switched on and the sufficient voltage of 8 volts and voltage of 8 is provided in the battery illuminator. So the commentator is thrown to the proper contact position by moving the handle like this and then the reading on the ammeter is made nearly 1.5 amperes. This is done by adjusting the rear start. I am just moving the rear starts jockey and when I move this jockey the reading on the ammeter is also moving. I am just making it 2 coincides with 1.5 amperes.