Complex sentence: In 1843 he and Thurber relocated to Norwich, Connecticut and in addition to armsmaking, built prototypes of Thurber's typewriter designed for the blind, disabled and those "nervous" about writing by hand.
Split into simpler sentences: In 1843 he and Thurber relocated to Norwich, Connecticut. Inaddition to armsmaking, they built prototypes of Thurber's typewriter designed for the blind, disabled and those "nervous" about writing by hand.