Editing Hermann von Helmholtz (section)

===Nerve physiology===

In 1849, while at Königsberg, Helmholtz measured the speed at which the signal is carried along a nerve fibre. At that time most people believed that nerve signals passed along nerves immeasurably fast.<ref name="glynn">{{cite book |last1=Glynn |first1=Ian |title=Elegance in Science|year=2010 |publisher= Oxford University Press|location=Oxford|isbn= 978-0-19-957862-7|pages=147–150 }}</ref> He used a recently dissected sciatic nerve of a frog and the calf muscle to which it attached. He used a [[galvanometer]] as a sensitive timing device, attaching a mirror to the needle to reflect a light beam across the room to a scale which gave much greater sensitivity.<ref name="glynn"/> Helmholtz reported<ref>Helmholtz, Hermann von (1850).''Vorläufiger Bericht über die Fortpflanzungs-Geschwindigkeit der Nervenreizung''. In: Archiv für Anatomie, Physiologie und wissenschaftliche Medicin. Veit & Comp., pp. 71–73. [http://vlp.mpiwg-berlin.mpg.de/library/data/lit29168 MPIWG Berlin]</ref><ref>Helmholtz, Hermann von (1850). ''Messungen über den zeitlichen Verlauf der Zuckung animalischer Muskeln und die Fortpflanzungsgeschwindigkeit der Reizung in den Nerven''. In: Archiv für Anatomie, Physiologie und wissenschaftliche Medicin. Veit & Comp., pp. 276–364. [http://vlp.mpiwg-berlin.mpg.de/library/data/lit1862 MPIWG Berlin]</ref> transmission speeds in the range of 24.6 – 38.4 meters per second.<ref name="glynn"/>