Irons Unit: Light and Heat

Doing the ironing could be very dangerous because irons need to be hot to press clothes flat.  The big 'box iron' on the left of the photo was filled with hot coals from the fire.  The other irons are called "sad irons" and were heated on the stove or in the fire.  The word 'sad' used this way means 'heavy or dense', not unhappy.  In 1870 an American housewife called Mary Potts invented an iron that stayed hot for longer with a wooden handle to prevent the user from getting burned.  It made ironing a lot safer and easier.  Her invention, at the top right of the photo, became famous as the 'Mrs Potts iron'.