Path: utzoo!attcan!uunet!convex!killer!ames!nrl-cmf!mailrus!cornell!uw-beaver!tikal!sigma!bill
From: bill@sigma.UUCP (WIlliam Swan)
Newsgroups: sci.electronics
Subject: Re: History-- series streetlamps
Message-ID: <1804@sigma.UUCP>
Date: 30 Sep 88 20:46:46 GMT
References: <7200013@silver>
Reply-To: bill@sigma.UUCP (WIlliam Swan)
Organization: Bob Williams for Governor
Lines: 15

In article <7200013@silver> commgrp@silver.bacs.indiana.edu writes:
>Old-style incandescent streetlamps were wired in series.  I always 
>wondered how such a system could work. I finally learned the method 
>which kept the lights on when a bulb burned out:
>[...] Above each lamp socket was a pair of spring-loaded 
>contacts separated by a piece of waxed paper.  If one bulb burns out, 
>the voltage goes up, the paper arcs through and burns away, forming a 
>short circuit. [...]

This is essentially the same mechanism used in Christmas tree series
light strings.


-- 
William Swan	..!tikal.teltone.com!sigma!bill