Underwood typewriters have a long, respectable history. First making their debut in the 1890s, Underwood typewriters went on to be the typewriter of choice for offices, news services and authors around the world. Frequently, the spring line on older typewriters will break after many years of use. The spring line is a string attached to a rotating spring that advances the typewriter forward with each key you press. In order to have a working typewriter, you will need to access the spring to re-string your typewriter by removing the carriage.
Look to the far right of your typewrite as it sits on your desk.
Pull the top right lever on the carriage and slide the carriage to the left.
Flip your typewriter upside down and look under the carriage. You should see a metal flap or button.
Press the flap or button and slide the carriage to the right. It should slide off.