Convert from block [Midwest U.S.] to chain [Ramsden, engineer]

Unit Definition (block [Midwest U.S.])
The Block is an informal unit of distance popular in the U.S. A block is the average distance between street intersections in the rectangular street grids common in most American cities. The length of a block in many midwestern USA cities is about 1/16 mile or 100 meters.

Unit Definition (chain [Ramsden, engineer])
The Ramsden chain is quite different to the Gunter chain. The Ramsden chain was commonly used by American surveyors. It equals approximately 100 feet and is also known as the engineer's chain.