Bathroom scales are first introduced, inviting people to weigh themselves in private.
Date: 1913
Prior to this, most people didn't know their own body weight, as the only option for weighing themselves is in public locations with penny scales. The introduction of bathroom scales opens the way for weight to be increasingly used as a measurement of health, with different strategies of shame and control as people begin to be seen as responsible for "losing" or "gaining" weight.