Suppose that you are measuring the distance between point A and point B with a 100-ft tape, and the distance is less than 100 ft. Suppose that you are the head chainman. To start off, you and the rear chainman are both at point A. You walk away from point A with the zero-foot end of the tape. Because this is a plus tape, the tape has an extra foot beyond the zero-foot end, and this foot is subdivided in hundredths of a foot, reading from the zero.

You set the zero on point B, or plumb it over point B; then call out, "Take a foot!" When the rear chainman hears this, he pulls back the first even-foot graduation between A and B to point A, or plumbs it over point A. Lets say this is the 34-ft graduation, The rear chainman calls out, "Thirty-four!"

You now read the subdivided end-foot graduation that is on or over point B. Lets say it is the 0.82-ft graduation. You call out, "Point eight two! The rear chainman rechecks the even-foot graduation on point A and calls out, "Thirty-four point eight two!" As you can see, your subdivided-foot reading is added to his even-foot reading; hence, the expression "plus" tape. Suppose now that you are measuring the same distance between the same points, but using a "minus" tape; that is, a tape on which the subdivided end-foot lies between the zero-foot and 1-ft graduations. This time when you walk away with the zero-foot end, you set the 1-ft graduation on point B and call out, "Take a foot!" When he hears this, the rear chainman again hauls back the first even-foot graduation between A and B to point Abut this time this will be the 35-ft graduation. So the rear chainman sings out, "Thirty-five!" When you hear this, you read the subdivided-foot graduation on point B. This time this will be 0.18-ft graduation, so you call out, "Minus point one eight!" The rear chainman mentally subtracts 0.18-ft from 35.00 ft and calls out, "Thirty-four point eight two!" When you are also acting as the recorder, recheck the subtraction before you record the distance in the field notebook.