Dag Anouk en Bob,

Ik weet ook niet wie dat ding heeft uitgevonden, maar ik ben eens Engels gaan googlen. Dit vond ik na wat langer zoeken:

Inventions

Rather often, we teach things much as we were taught them. So the ‘best way to teach’ something seems natural, obvious, inevitable. But in fact every way to teach a given idea or skill was once invented by someone, and passed on to others. In science their traces are often to be seen in the science teaching apparatus stored in the laboratory cupboards.

Some of these inventions diffuse rather widely. The UK school inspector R.A.R. Tricker invented a large demonstration ‘circuit board’ for teaching simple dc circuits. Ted Wenham modified it to become the ‘Worcester circuit board’ for individual use by pupils. Martin Harrap invented the idea of electrical ‘puzzle boxes’, designed for students to try to find out what circuit elements they contained by measurements on their external terminals. Both were introduced as part of two Nuffield projects. Today, one can see ‘circuit boards’ and ‘puzzle boxes’ mentioned in any syllabus as unproblematic and obvious potential teaching tools. PSSC invented the ‘ticker timer’ for recording accelerated motion, and versions of it swept the world.

PSSC is de Physical Sciences Study Committee, en Amerikaanse commissie die na de tweede wereldoorlog curriculae moest ontwikkelen voor exacte vakken op de Amerikaanse Highschools.

 De tijdtikker lijkt dus door die commissie te zijn geïntroduceerd. Misschien niet uitgevonden, maar dan toch zó omgebouwd dat ze voor dit soort dingen bruikbaar werd. Want eigenlijk is de tijdtikker in principe niks meer dan een ouderwetse deurbel met een carbonpapiertje. 

 Groet, Jan