Light was a valued commodity in the early 19th century, when Charles Carroll Jr. was building and furnishing Homewood, his family's splendid five-part Federal-style house. The siting and plan for what is now Homewood House Museum acknowledge the importance of daylight, and interiors of houses of the day were perhaps influenced more by light than by any other factor: Paint colors, furniture finishes, hardware, mirrors, gilt frames, cut glass and silver objects were all designed and chosen for their ability to reflect limited light.

For the next 10 weeks, the search to capture light in the late 18th and early 19th century will be examined in O Say Can You See? Revolutions in Lighting Technology, the 2003 focus show that opens Thursday, Jan. 16, with a reception from 5 to 7 p.m. at the museum.

This student lamp was designed to help reflect candlelight onto one's reading or writing. The tinted reading glasses were supposed to prevent eyestrain.

Catherine Rogers Arthur, curator of Homewood House, says that a focus show such as this "provides an exciting opportunity for an in-depth study using an object from the museum's collection as the starting point."

The exhibit includes examples of the wide variety of lighting devices that would have been available to Carroll. Some of the earliest advances in technology were designs that improved candlelight by preventing flickering of the flame, or magnified it by using a silver or mirrored reflector. Oil lamps were another widely used form of artificial lighting, and many innovations to the wick, the fuel, the burner and the fixture itself revolutionized the way that people lived after sunset.

The exhibition continues through March 30; lectures, lighting demonstrations and gallery talks will help illuminate the subject. Details on upcoming events, planned for February and March, will appear in the Johns Hopkins online calendar, accessible from the university home page at http://www.jhu.edu; on the museum Web site, http://www.jhu.edu/historichouses; and in The Gazette.