1278
ANALYTICAL CHEMISTRY
cases it is desirable to calculate particular solutions for each problem and this direct solution can he accomplished by reiteration in about 6 minutes. Two photographic views of the Miniac computer are presented in Figures 5 and 6. Time Requirement Comparison. Three methods of obtaining mass spectrometric results have been employed over the past few years a t this Iahoratory: photographic record plus analog
Table 11. Time Requirements for Various Methods of Measuring and calculation of Mass Spectrometer Data (Basis. 30 20-component gas samples) PhotogrsDliio Time Record Photographic Requirement. Analog Record Man-Hours CornLlutcr 602A (IBM) 10 Instrument' 10. Chart measurement 10 10 Csleulation 30 7.5 T n. t~.~ al 60 27.5 . Man-hr./sample 1.65 0.92 II This includes sample oharging and poml,-oiit.
Sadie CPC (IBM) 8 0 3
calculator reduced this still further, to 0.37 man-hour. These figures include time for instrument pump-out, sample charging, checking, eto. It is now possible with 11/2 men, one mass spectrometer, digital conversion, and card programmed calculator computation t o report 30 gas samples (20 components) per &hour shift. ACKNOWLEDCMENT
The authors wish to thank the Atlantic Refining Co., Phil* delphia, Pa., for the photographs and description of the encoder and digital computer used in their system. LITERATURE
