Slide all three sliders on the measuring scale to the left, with the flat, disk-like pan also situated on the left.
Turn the screw under the pan on the left until the right-hand indicator is balanced on the center mark. This is required to calibrate the triple beam balance.
Place the object on the pan. You should notice the indicator move up.
Slide the largest slider, which is the 100-gram one, to the right until the indicator drops down below the center mark. Move the slider back one notch to the left. The indicator should rise above the center mark again. Make a note of the notch measurement, which will say something such as 600 grams.
Repeat the process with the second largest slider, which is the 10-gram one. When the indicator drops below the center mark, back up one notch and read the measurement, such as 70 grams.
Slide the smallest slider, the 1-gram one, to the right until the indicator is perfectly balanced on the center mark. This slider is the only one that is not notched, so you can move it anywhere. Once balanced, read the precise measurement, which can be something such as 3.4 grams.
Add all three measurements together to get the total mass of the object. In the examples, you would add 600 grams plus 70 grams plus 3.4 grams, resulting in a total mass of 673.4 grams.