solidated data for manual sorting. Until recently the nearest approach to the proposed system has been to use a spectrophotometer with chart reduction features and to record infrared spectra directly on punched cards. This system does not allow superimposition of two or more spectrograms for exact comparisons. The new method uses a standard microfilm aperture card and employs features of summary printing made possible by such equipment as the IBM Type 557 interpreter. This permits combining of Wyandotte-ASTM index cards for empirical formulas and chemical names and spectral data-chemical structure cards. In addition, it supplies a 35-mm. reduction of the original spectrogram which can be enlarged to full size on standard viewers or reproduced photographically at low cost. The system is now used extensively to solve problems of filing and reproducing engineering drawings. Literature describing this application is available (page 101 A, L - l ) . The system involves microfilming each spectrogram on equipment such as the Recordak system and mounting the positive film in an aperture card. The indexing on the aperture card can be copied from the source document, code sheet, or the film image itself. The film is cut precisely and mounted on the card by a manually operated unit. For multiple sets of reference cards, a negative microfilm is made first and positives are made from the negative. Tabulating equipment can be used to reproduce punch and interpreter units. Enlargement of the film can be made by standard photographic methods. I t is generally easier, however, to use modern microfilm readers which allow reference to two images at the same time. ' With a reader, translucent spectral graphs can be overlaid on the screen for comparison (see photo). Advantages cited are that the system provides an economical method of combining coding and data chart on one standard file card; minimizes duplication of effort by providing standardization; promotes uniform system of filing spectral data; stimulates exchange of data and makes such exchange more efficient; and reduces time spent in filing and searching. Aperture card documentation has potential applications in several fields, including: infrared, ultraviolet, and visible absorption spectroscopy; x-ray diffraction, nuclear magnetic resonance, fluorescence, mass, and Raman spectroscopy; crystallography, gas chromatography, analytical chemistry methods, documentation, and reproduction of molecular structure diagrams, and physical testing methods instrument records.
For growing laboratory needs, a growing TEMCO line
NEW high-capacity high-temperature TEMCO Electric Furnace • Ideal for long "waste" space Chamber sire:
work parts...no to be heated.
1 3 - M ' deep 4 - A * high 4-i," wide • Choice o< 2000° or 2300°F maximum operating temperature... 1 15 or 230 V. Big power reserve for heavy loads, fast heating, quick recovery time. • Cosed in husky welded and reinforced steel shell. Easily operated door swings out and up.
Type 1900 TEMCO Furnaces are designed f o r the user who needs high temperatures but who does not want to buy more than he needs. Chamber is long in relation to its height and depth. Desigred for direct across-theline o p e r a t i o n . . . m a y be purchased either without controls or with any o f a wide selection of fine instruments. A convenient control " p a c k a g e " that may be attached to the side o f the furnace is also available. Price o f furnace alone, $ 2 1 5 or $ 2 3 5 , according to temperature range. Write for information
THERMO
and name of nearest dealer.
ELECTRIC
MFG. CO.
4 7 8 Huff Street, D u b u q u e , I o w a Circle No. 28 on Readers' Service Card
Ferrocene (Dicyclopentadienyliron) . . . An unusual compound with interesting properties.
SPECIFICATIONS Appearance and Form: Orange, Crystalline solid with camphor-like odor Melting Point:
173° -174" C.
Solubility:
Insoluble in water, slightly soluble in benzene, ethanol ether and petroleum ether.
Ferrocene (MC&B 8758) is the parent compound for a novel group of organic metallic compounds. It displays stability and other properties of aromatic compounds. Some of the reactions it undergoes are also typically aromatic. Although not commercially used, it shows significant anti-knock properties when added to motor fuels. Available from MC&B and MC&B Distributors at $17.50/10g.
Matheson Coleman & Bell D i v i s i o n of T h e M a t h e s o n C o m p a n y , I n c . Norwood (Cincinnati), Ohio; East Rutherford, New Jersey VOL. 3 1 , NO. 4 . APRIL 1959
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67 A