The Measurement of Chromospheric Heights

A method is proposed for the photOelectric measurement of chromospheric heights which requires neither high telescopic resolution nor the very best seeing. It employs slicing of the solar image, controlled oscillation of oppo~ing solar limbs at the spectrograph slit, and feeding of the photoelectric output to a digital storage oscilloscope. Trials with the apparatus during September 1967 at the Snow telescope yielded estimates of limb heights in H~3 and in the H-line of Ca I