# Page:Popular Science Monthly Volume 90.djvu/292

�How Much Does That Cloth Cost?

As the clerk measures off the goods this intelligent measuring stick registers the cost of each yard and a fraction of a yard

��The measuring stick is a yard long and has two scales on it, one in inches and the other in ratios of from one- eighth to fourteen and three-fourths yards

���10 yds.

��yard cost as is desired. In this respect the four sheets are exactly alike. They differ in the figures along the bottom of the sheet which represent yards in fractions of quarters. The sheet to the extreme left takes up a space along the ratio scale of two and three-quarter yards. The next

sheet or roll takes up from three to six and three-quarter yards ; the one next that from .seven to ten and three-

���This roll gives cost of goods from to 2J4! yds. long

�� ��A MACHINE has been designed to eliminate losses made by store clerks in over measuring and in calculating the cost of fractional yards. It consists of two main parts — a measuring stick attached to the edge of the counter and a series of four rolls of paper with sets of figures on them. These rolls of paper are spring-operated.

The measuring stick is just one yard long. It has two scales on it. That nearest ^the edge of the counter is in inches, running from zero to thirty-six inches or one yard. The other scale is laid off on the edge of the stick farthest away from the counter edge. It takes up almost thirty-six inches, but it is laid off to a certain scale or ratio to repre- sent from one-eighth to fourteen and three- quarter yards. Thi3 scale is divided into four equal parts as indicated by the arrows. One of the rolls of paper mentioned is fitted between each of the arrows.

Each roll surface is divided off into a series of rectangles with figures in each. The figures in the left and right border rectangles of each sheet or roll represent the cost of the goods in cents, beginning with two cents and going up to as high a

��quarter yards and the one on the extreme right from eleven to fourteen and three-quarter yards. . The figures along the bottom of each sheet correspond with the yardage of the ratio scale. The figures in the rectangles, between the side and bottom figures, represent the cost of the goods in dollars and cents. Each cost figure is the multiplication of the bottom figure by that of the cost per yard on the same level line as the final cost.

The clerk measures off the goods a yard at a time. If the purchase is ten yards, the third roll is pulled out from the left. If the goods costs fourteen cents a yard, the figure fourteen is found in the left-hand border column, reading across to the right until the clerk comes to the vertical column with the figure lo at the bottom. Then the cost is found to be \$1.40. Other frac- tional yards and fractional cents purchases are found in the same easy manner.

There are stops at each end of the meas- uring stick to prevent the clerk from meas- uring more than a yard at a time. The rolls of paper pull out and roll up again like ordinarv roller shades.

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