In the Welcome Forum Eddystone stated he is seeking to obtain an electric/acetylene autochanger. As he describes, this device was used for an electric light and would automatically change to acetylene when the bulb burned out.
I am not familiar with such a device. I did find on the web that Donaghadee light on the northeastern coast of Ireland had one of these installed in October 1934 when this light was automated. A standby acetylene light was “fitted to the lamp changer” and would operate automatically if the electric lamp failed or electric supply failed. The acetylene light was discontinued in 1967 when a standby generator and a two-bulb lamp changer were installed.
This question comes to mind. What caused the acetylene light to come on when the power failed?
I am assuming the acetylene pilot light ran continuously but some device existed to cause the main acetylene supply valve to open when the electric power failed. A heat sensing device, perhaps, activated the acetylene lamp when no heat was present from the electric light bulb.
Also, were any U.S. lighthouses ever equipped with acetylene standby lamps?