Understanding what is being measured and how is only half the battle. And if you are (were) still confused (after my last post), don’t worry, so am (was) I.
Once you put your foot in the shoe, how should it fit? How should it feel? You may be unsure. Perhaps you think you have always worn shoes that are too tight or too long. Unlike a car, you cannot test drive a pair of shoes – and the reality is the shoes will change as you wear them. Plus your feet will change as you walk on them. Equally, for us in the shop, we cannot always see how your foot fits inside the shoe and we certainly cannot feel how the shoe feels on your foot.
The original, and probably still the best, way to answer these questions is a dialogue between you and the shoe salesperson. But there have been a few attempts at improving the experience along the way, not all of them successful.
Shoemakers started out with a size stick with a mark or notch for each size, something like a wooden ruler, but by the twenties (and into the thirties, forties and fifties), you may well have been asked to place your feet (and shoes) into a shoe fitting fluoroscope. Most likely an invention born from the need to diagnose soldiers’ quickly during the First World War (with their boots still on), this involves standing on an x-ray tube with the shop assistant seeing an outline of your shoes with your feet inside them: a good idea in theory, less good for the salespeople who were regularly exposed to the radiation.
The era also saw the introduction of the slightly less impressive, but certainly more enduring Clarks foot gauge device. And in the US, in 1926/27, Charles Brannock patented the Brannock device (foot gauge) which came complete with yet another sizing system.

Nowadays, companys such as Lodger, Left Foot Company and Rivolta are applying laser scanning technology to the problem. At Lodger we use our scanner to match precise measurements of your feet to our library of lasts, giving you added confidence and the ability to order sizes we may not stock.

[Next time, Clement and I will give you our personal tips for how to judge if a shoe fits.]

[...] up on previous posts on how feet are measured and how shoe sizes work, here are some tips from myself and Clement in the Lodger store on finding [...]