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We have observed examples of each of the three limiting cases of electric field induced line shapes predicted by Bridge, Haner, and $Dows1$ in electric field induced infrared absorption bands of $HCN1$ in addition to two types of induced transitions not allowed in the absence of a field. The spectra were obtained using a light-guide type of Stark cell of length 1 meter, alternating electric field of 45 Hz of amplitude 30,000 volts/cm, and phase sensitive detection at 90 Hz. Sample pressure was approximately 10 torr of HCN plus about 1/2 atmosphere of $SF6$ to prevent electrical breakdown. This research has been supported by NSF. Present address of P. L. Willson: Center for Naval Analyses, University of Rochester, Arlington, Virginia, 22209. $\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}$N. J. Bridge, D. A. Haner and D. A. Dows, J. Chem. Phy, 48, 4196 (1968).