o (110 x 30 mm), paper loss to right margin with loss to final few letters of nine lines, small tear to lower right margin, affecting 1 or 2 words of text. With two-line autograph note at top of page 1 by the physiologist Johannes Mller; autograph note signed at top right, by Johann Franz Encke, Secretary of the Berlin Academy." /> HELMHOLTZ, Hermann von (1821-1894). Autograph manuscript signed ("H. Helmholtz"), "Vorlafiger Bericht ber die Fortpflanzungsgeschwindigkeit der Nervenreizung". Knigsberg, [before 21 January 1850]. 2 pages, 4<V>o (110 x 30 mm), paper loss to right margin with loss to final few letters of nine lines, small tear to lower right margin, affecting 1 or 2 words of text. With two-line autograph note at top of page 1 by the physiologist Johannes Mller; autograph note signed at top right, by Johann Franz Encke, Secretary of the Berlin Academy. | Christie's