Ignition tube
（重定向自Fusion tube）
![An illustration of a setup using an ignition tube. The ignition tube is being heated by the Bunsen burner on the left, with the heated gas escaping from the tube to the pan via the delivery tube on top and at right.](/Images/godic/202501/14/Ignition_Tube4259.png")
An ignition tube is a piece of laboratory equipment. It is a laboratory tube used much in the same way as a boiling tube except not being as large and thick-walled. It is primarily used to hold small quantities of substances which are undergoing direct heating by a Bunsen burner or other heat source.