Source of the photo
http://www.thermo.com/com/cda/products/image_popup/0,2772,10122277-Next-0-1,00.html
Author of the description
Fenyvesi Éva
Gas-Chromathography combined with Mass Spectrometry, gives both quantitative and qualitative information on the sample. The components separated by gas chromatography get into the mass spectrometer and are identified by comparison of their characteristic spectra to the spectral library.