What is "ignition tube"

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.

Ignition tubes are used in the sodium fusion test.

Ignition tubes are often difficult to clean due to the small bore. When used to heat substances strongly, some char may stick to the walls as well. They are usually disposable.