Steps To Massing an Object Using The Cent-O-Gram Balance   1. Move all sliding masses all the way to the left. 2. Adjust the taring knob until the center line of the pointer,points to the zero. You turn the taring knob away from you to make the pointer move up and visa versa. Before you ever put anything on the balance , you must be sure that the balance reads zero when nothing is on it. This is called " taring the balance".( also called zeroing the balance) 3. Now place the object in the pan.( no hot objects ! ) 4. Move sliding masses ,starting with the heaviest sliding mass and continue to the lowest one . The three upper sliding masses fit into notches. 5. The smallest sliding mass moves along a scale whose divisions are 1/100's of a gram ( .01 ). Therefore when you apply the estimation rule, you can estimate to one tenth of one hundreth, which is one thousandth ( .001 ) of a gram. All of your mass measurements must be done to three decimal places. 6. To estimate to the thousandth's place more accurately, stand behind the balance, and look down to exactly where the smallest sliding mass is pointing. 7. The mass of the object is equal to the sum of all the sliding masses as seen on your balance.