Some useful tips to study a leveling rod marked in decimal feet
The Illinois Professional Land Surveyors Association has presented this useful construction video tutorial to teach you how to study a leveling rod with measuring units in decimal feet. In the leveling rod, the fractional parts of a foot are labeled from 1 to 9. If the measuring units of the rod are provided in inches, the numbers 10 and 11 are located below the red number.
Here, decimal feet is used to make calculation simple. The extreme bottom end of the rod is taken as the zero end and so, all the selected measurements or height will be over the surface on which the rod is rested.
Each black mark on the rod contains equivalent height similar to white space. It allows you to take your readings at the edges of the marks and spaces. Therefore, with the help of regular mark heights, it becomes easier to study the rod from a few hundred feet distant.
The reading that has been taken on this level rod does not belong to an elevation rather it is simply a vertical distance among the instrument line-of-sight and the surface on which the rod is rested. With the selection of readings of two rods, it is possible to determine the variation in elevation among two points. Here, the elevation variation becomes 1.32 feet.
To have more information on this leveling rod, go through the following video tutorial.
Video Courtesy : Illinois Surveyor