of each image is $z = 2.639 \pm 0.002$ (Lawrence   1995a, hereafter LEJT95; see also Katz & Hewitt 1993, hereafter KH93; and Lawrence 1996). The lens appears to be a single elliptical galaxy labeled G (Schechter & Moore 1993, hereafter SM93). Its redshift remains undetermined; attempts with the Keck I telescope initially appeared successful, but later were shown to be a misidentification of Fe II lines at the redshift of the QSO (Lawrence  1995b) as Na D lines at $z \sim 0.5$. The QSO images are exceedingly red, and extinction in the lens galaxy is suspected of being significant (LEJT95).

To further study , we undertook a series of observations with the Hubble Space Telescope (HST). We describe our observations in §2, as well as our reduction and analysis of the “raw” HST images. In §3, we give our astrometry and photometry results for the components of the system. We present a detailed analysis of the properties of the images, with models that account for most of their observed properties in §4. Finally, our conclusions follow in §5.

Observations
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We used WFPC2 to obtain 9 deep, high-resolution images with two broad-band filters, F675W and F814W, which are similar, respectively, 