Drawing of a light bulb from Carl Heinrich Florenz Müller: 1) evacuated bulb, 2) carbon fibre filament made of cotton clamped with copper tubes to 3) platinum wire connectors, 4) glass holder and bushing for connectors.
SVG-drawing by <a href="//commons.wikimedia.org/wiki/User:Xorx" title="User:Xorx">Dr. Schorsch</a>
Drawing after a figure in Meyers Konversationslexikon