This is a Hammond 'Ideal' typewriter made in New York in about 1893 by the Hammond Typewriter Company. This firm produced typewriters from the 1880s of which consumers could decide on either a three-row, double shift QWERTY keyboard or this two-row curved one. The Hammond typewriter also had a feature which allowed typists to see their typing by a ribbon vibrator which raised or lowered the ribbon with each key stroke.
During the 1880s and 1890s the keyboards on typewriters were not standardised. Typewriters were generally sold to offices which by then had not been staffed with typists. Since the sale of a new machine usually meant training a new typist, manufacturers could compete using alternative keyboards. In the USA as late as 1923 typewriter manufacturers operated a placement services for typists and it was in their interest to develop machines with keyboards which did not require as much training.
Newmark, Craig (ed), 'Readings in Applied Microeconomics: The Power of the Market', p.219