Pace count beads

Pace count beads or ranger beads is a manual counting tool used to keep track of distance traveled through a pace count. It is used in military land navigation or orienteering.

The tool is usually constructed using a set of 13 beads on a length of cord. The beads are divided into two sections, separated by a knot. 9 beads are used in the lower section, and 4 or more beads are used in the upper section. There is often a loop in the upper end, making it possible to attach the tool to the user's gear with a simple Larks head hitch.

There are two ways to use the beads. One is to represent the paces the user has walked, while the other is to represent the distance walked.

Both methods requires the user to know the relationship between the paces walked and the distance travelled.

As users walk, they typically slide one bead on the cord for every ten paces taken. On the tenth pace, the user slides a bead in the lower section towards the knot. After the 90th pace, all 9 beads are against the knot. On the 100th pace, all 9 beads in the lower section are returned away from the knot, and a bead from the upper section is slid upwards, away from the knot.

In this manner, the user calculates distance travelled by keeping track of paces taken. To use this method, the user must know the length of his pace to accurately calculate distance travelled. Also, the number of paces to be walked must be precalculated, or the distance travelled has to be calculated from the walked paces.

For every 100 metres the user walks, one of the lower beads is pulled down. When the ninth of the lower beads is pulled, the user has walked 900 metres. When the user has walked 1000 metres, one of the upper beads is pulled down, and all the lower beads are pulled back up.

Using this method the user must know the number of paces walked in 100 metres. An experienced user can also adapt the pace count for each hundred metres depending on the terrain. When using this method the user does not have to calculate or look up how long a distance to walk or the distance travelled.

This method can of course be used for non-metric distances as well, though with the beads arranged in a different manner.

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Wikipedia