For this example we'll be looking at measuring the voltage across our resistor, using an analog voltmeter instead of a digital multimeter. The simple circuit consisting of a light bulb and a rear stat is used in this example. A rear stat is a variable resistor. For this example, the rear stat's resistance can be adjusted by moving the slider at the top. When connecting the voltmeter, one lead should always be connected to the negative terminal, while the other lead must be connected to one of the three positive terminals. The choice of which terminal to use depends on the required range of measurement. The three scales displayed on the voltmeter correspond to the three positive terminals, three volts, fifteen volts and three hundred volts. When reading the voltmeter, ensure that the correct scale is read. The bottom scale has a range of minus one volt to three volts, and is used when the lead is plugged into the three volt terminal. The middle scale has a range of minus five volts to fifteen volts, and is used when the lead is plugged into the fifteen volt terminal. Finally, the top scale has a range of minus one hundred volts to three hundred volts, and is used when the lead is plugged into the three hundred volt terminal. The voltmeter should always be connected in parallel to the resistor to be measured. In this example, the source has a voltage between three and fifteen volts, so we're going to use the middle positive terminal. Unlike the multimeter, the analog voltmeter's positive and negative ranges are not the same, so you may need to switch the leads around if you're getting a negative reading. When reading the resistance of the rear stat changes the voltage measured by the voltmeter.