|Pierre Vernier metrology|
- Pierre Vernier added a secondary scale
- to the moving part of a caliper,
- where each division on the moving scale
- is a constant fraction of divisions on the fixed scale.
- When divisions of the moving or “vernier” scale
- are nine tenths of the divisions on the fixed scale,
- then where the vernier scale aligns with the fixed scale
- gives you tenths to be added to mark preceding the zero.
- If humans had a superpower
- it might be in detecting alignment of lines
- more accurately than the optical ability of the eye.
- We can detect differences of alignment
- smaller than the size of the receptors of our retinae.
- This hyperacuity gets better with training
- but worsens with age and changes of attention
- and may not be the same from eye to eye.
Training a straw man
- Some people don’t like to think
- we need to be trained; instead,
- we are shown how, or we are taught.
- We don’t try to herd cats;
- we don’t put zebras to the saddle.
- We train dogs, not ourselves.
- Why don’t we admit, as the most
- domesticated animal on the planet,
- we are more like dogs than cats?