Here is something I found when I was moving house that I never knew I still owned. It's a switched double lamp adapter, these were pretty common here in NZ in the earlier days of domestic electricity supply:
As well, there was a small plug that fits into the light socket and you can run a 2 core flex to another light or small appliance, if the need arises:
The two side by side, for size comparison:
These devices were banned in the early 1980's here, mainly because of people lashing up all sorts of wierd looking installations, usually in home workshops. The plug itself was banned because it could not ensure that the polarity would be correct every time it was connected, also there was no earth contact.
Just a little question here, Bakelite, it it able to be moulded(sp??) or are all the bits machined from a block?. Paul, Yeah the same thing here used to happen here, as well as the odd adapter with two or three cords coming out of them, they were nasty things as far as DIY "improvisation" went.
I've seen various references to the non compliance of using bayonet plugs for appliances in the past but wasn't aware of any attempt to ban them...they would still be required for DIY pendant light fittings. I'm fairly sure I've seen HPM bayonet plugs for sale of late...or have they gone the way of piggyback plugs? Actually, if an appliance is properly designed it should be able to work safely with either polarity....the lack of earth is still a problem though...I've seen (and used) bayonet to 3 pin socket adaptors where no other source of power has been available. As for the bayonet double adaptor, I've often used them simply to run two light bulbs with the advantage if one burns out you've still got light.
I've seen various references to the non compliance of using bayonet plugs for appliances in the past but wasn't aware of any attempt to ban them...they would still be required for DIY pendant light fittings. I'm fairly sure I've seen HPM bayonet plugs for sale of late...or have they gone the way of piggyback plugs?
I think 'Bakelite', invented by Belgian-American Dr Leo Baekeland, was molded as a powder, originally with a woodflour-filler added to the phenol-formaldehyde mix. The high pressure / heat process required has made it uneconomic in competition with the more easily molded thermoplastics. BTW it sets to polyoxybenzylmethyleneglycolanhydride!
Also, the compression-molded plastics like phenolic and urea tended to come out of the molds with varying degrees of sharp-edged flash. This necessitated moving the parts to and from cleaning operations that are not necessary with the injection-molded parts.
The base materials are very aggressive chemicals. That, and the technique of grinding up the sprues and other wastes for 'filler' material, caused dermatitis in factory workers, and worse. High pressure is required as the reaction is barely controllable and produces volumes of gasses as the cure proceeds. Bakelite does not melt, it is 'thermo-setting', probably the first true commercial plastic. Needless to say, trawl the net and sure enough our bretheren in India and China are making artifacts with it still.
I seem to remember when Ma plugged in her electric iron, our unit had a switch built in to turn off/on the side outlet.