  We present photometry and spectroscopy of the soft x-ray transient Aql X-1.
Optical photometry during an active state shows a strong (0.6 mag peak-to-peak)
modulation at a period of 19 hours. Infrared (K'-band) photometry during a
quiescent state limits any ellipsoidal variations to <0.07 mag (peak-to-peak),
which implies an inclination i<31 (90% limit). Spectroscopy in a quiescent
state shows at most very small radial velocity variations, which implies a very
low inclination of i<12 (90% limit). The low inclination is rather unexpected
given the large photometric modulation seen in the active state. The upper
limit to the equivalent width of the anomalous Li 6707A line is <0.3A, which is
similar to the measured strength of this line in several other x-ray
transients.
