A technique has been developed and specifically optimized for routine quantitative analysis of small gas bubbles in glass using a quadrupole mass spectrometer. Bubbles as small as 40 microns in diameter have been analyzed using special sample preparation procedures and a bubble fracturing device that minimize the production of new glass surface. Calibration is accomplished by a direct method of gas injection and the analysis is performed during continuous evacuation. Sensitivity limits are determined to be 3 to 8 x 10^-4 nL of gas at standard temperature and pressure. Sample analyses are given. -- AATA