Do not handle sharp or hot objects with a baby in the sling. (howtoadult.com)
Oven mitts, lightly insulated hand coverings used to protect the wearer from hot objects in the kitchen, were invented in the early 1870s by, appropriately named, Texan baker Earl Mitt. (howtogeek.com)
«Hotter objects emit most of their radiation at shorter wavelengths: hence they will appear to be bluer while cooler objects emit most of their radiation at longer wavelengths.» (wattsupwiththat.com)