This engineering solution is attributable to Langensperger in 1816, but was patented by arrangement in London, in 1817, by Rudolph Ackermann, whose name stuck to it.
This engineering solution is attributable to Langensperger in 1816. This engineering solution was patented by arrangement in London by Rudolph Ackermann. This was in 1817. Rudolph Ackermann's name stuck to it.