How can I increase light in a dark hallway?

tract lighting comes in all types and can be used in the hall to spread light.

Without a picture I will offer a coupe of solutions. You could mirror a console tabĺe top to reflect light as well as a trio of mirrors on the wall. Alternatively paint is your friend. Choose a light colour with some sheen to bounce the light. A pearlescent or metallic finish on one or more walls will help also.

Paint a bright or light color, change any light fixtures to ones that have a higher wattage, leave doors open to all adjoining rooms.

This may seem obvious, but make sure any light fixtures are clean (not dusty) and use bulbs with a high lumen output. Older fixtures designed to take a maximum of 40 watt bulbs can produce much more light with a halogen, CFL or LED bulb, because those bulbs are more efficient and burn much cooler. You can replace an old 40 watt bulb that put out 450 lumens with a 1600 lumen LED bulb, and that LED will still only be 22 watts.

You could also install a skylight