Deletion of Ramsden's square chain

Comment: to Chain (unit)#Ramsden's chain and possibly add a little more information about what "square" means. A chain consists of 100 links (each link is a length of metal; they are linked together)—see Gunter's chain. Links were different sizes at different places/times. A "square chain" is the area of a square where the length of each side is one chain. See rticles for deletion/Aum (unit) for more information
Stance: merge
Cited policy: Wikipedia:Attribution (WP:A)