Convert line (button makers) to light day
Selected category: length.
Definition and details for line (button makers):
U.S. button maker use the "line" unit of length to measure buttons. This unit is equal to 1/40 inch or 0.635 mm. It was probably introduced by German immigrants, who used since ninth century a different version of "ligne" equal to 1/40 inch to measure buttons.
Definition and details for light day:
Light day is defined as the distance the light travels in one day through a vacuum. The defined light speed is c = 299,792,458 m/sec. So one light day equals to about 25.902 billion kilometers.