Engineer's chain (Ramsden's chain) A longer chain of , with a hundred links, was devised in the UK in the late 18th century by Jesse Ramsden, though it never supplanted Gunter's chain. Surveyors also sometimes used such a device, and called it the engineer's chain. or Texas chain In the Southwestern United States, the chain also called the Texas chain, of 20 (16.9164 m , or ft) was used in surveying Spanish and later Mexican land grants, such as the major Fisher–Miller and Paisano Grants in Texas, several similarly large ones in New Mexico, and over 200 smaller in California. Metric chains Metric chains, of lengths 5 m, 10 m, 20 m and 30 m, are widely used in India. Tolerances are +/- 3 mm for 5 m and 10 m chains, +/- 5 mm for a 20 m chain, and +/- 8 mm for a 30 m chain. Revenue chain In India, a revenue chain with 16 links and of length is used in cadastral surveys. Other instruments Also in North America, a variant of the chain is used in forestry for traverse surveys. This modern chain is a static cord (thin rope) 50 metres long, marked with a small tag at each metre, and also marked in the first metre every decimetre. When working in dense bush, a short axe or hatchet is commonly tied to the end of the chain, and thrown through the bush in the direction of the traverse. Another version used extensively in forestry and surveying is the hip-chain: a small box containing a string counter, worn on the hip. The user ties off the spooled string to a stake or tree and the counter tallies distance as the user walks away in a straight line. These instruments are available in both feet and metres. Use in popular culture The lyrics of Three Chain Road, by Lee Kernaghan, include the line "He lived out on the three chain road" which is the name of many Australian roads; referring to the width of the road reserve. References External links Math Words Units of length Imperial units Surveying Customary units of measurement in the United States Forestry tools