For your consideration is this early 1900 double student duplex wick kerosene lamp made in England with adjustable slide. The double student lamp became popular in the late 19th century, and they were made with double shades and were originally known as a reading lamp. The name "duplex" describes the two flat wick arrangement which was originally patented by Hinks in 1865 to give double the light from a burner with efficient combustion. The two knobs on each burner raise and lower the wicks with the lever on the opposite used for extinguishing the flame. The knobs are marked "Made In England, Duplex". The lamp features screw caps on the kerosene basins for easy filling. The knob on the middle shaft can be loosened and tightened to adjust the height of the two lamps. The lamps feature a green glass lamp shade and a clear glass chimney. One is missing. The whole lamp is constructed of brass and has a strong, sturdy hexagonal base. The lamp measures 20 1/4" L x 8" W x 24" H.