Question

What is a glowing splinter ? How does it indicate the presence of oxygen ?

Answer 1

Splint are basically thin and long strips of wood, about 12"long and 1/4" across. It is long enough to allow flame to be lit without risk user's hand.
Test for oxygen: The splint is lit, with the flame almost blown out. When it is exposed to high concentration of oxygen, the splint glows with a bright flame because oxygen supports burning. This is known as glowing splint test.