Edge-Notched Cards

It is possible that the future may also see the use of digital calculators in qualitative spectrometric analyses. Various types of punched cards have been used as a method of recording spectral data on pure compounds. The purpose of these files is to facilitate the identification of spectral data on unknown substances. Their use in infrared analysis has been covered by Mecke and Schmid (M6), Keuntzel (K3), and Baker, Wright, and Opler (B2). The last named authors describe a file of 3150 spectra which was expected eventually to be expanded to include up to 10,000 spectra. Zemany (Zl) discussed the use of edge-notched cards in cataloging mass spectra and Matthews (M4) describes a similar application in connection with X-ray diffraction powder data. These two applications made use of only hand-sorting methods the files of Baker et al. were intended to be processed by machine. 

Infrared spectra have been made available on Keysort cards under the auspices of the National Research Council (12). The large space in the center of edge-notched cards which is not used for holes and notches permits recording the spectrum in graphic form. Although sorting becomes cumbersome as the file increases in size, it is very convenient to have a search lead directly to the actual data desired—in this case, the infrared spectrum. 

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