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Observations of a number of helium triplet (?? 10830, 4713, 4471, 3889, 4026) and hydrogen (H?, d, ?, ?) emission line intensities in six quiescent prominences are presented. The regions of prominence and neighboring corona were raster-scanned by the telescope, and all lines were measured concurrently at each point. The instrumental field of view was 5? × 20?. The results are compared with previous observations and theory. In particular, the intensity of the ? 10830 emission relative to the other triplets is found to differ strongly from the predictions of the recent detailed calculations of Heasley et al. (1974) for model quiescent prominences.

The Mees CCD (MCCD) instrument is an imaging spectroscopy device which uses the 25 cm coronagraph telescope and the 3.0 m Coudé spectrograph at Mees Solar Observatory (MSO) on Haleakala, Maui. The instrument works with resolving power up to R ˜ 200 000 with significant throughput from ?3934 Å (Caii K) to ? ˜ 10 000 Å. A fast guiding active mirror stabilizes the image during observations. A rapidly writing magnetic tape storage system allows observations to be recorded at 256 kbytes s-1. Currently, the MCCD is used for imaging spectroscopy of solar flares at ?6563 Å (Ha), and velocity measurements of umbral oscillations; future plans include emission line studies of active region coronae, and photospheric studies of solar oscillations.