15:4015:40, 24 January 2013diffhist+430
Ball chain
Added references, since someone thinks references are needed, to the original 1914 patent and a more recent patent that addresses other issues. Reference tag therefore removed.
15:4015:40, 24 January 2013diffhist+430
Ball chain
Added references, since someone thinks references are needed, to the original 1914 patent and a more recent patent that addresses other issues. Reference tag therefore removed.