In 1877 Imperial Germany’s national patent office opened for business. Patent # 532 was for Nicolaus Otto’s four-stroke motor. jstor.org/stable/pdf/249…

In 1877 Imperial Germany’s national patent office opened for business. Patent # 532 was for Nicolaus Otto’s four-stroke motor.
jstor.org/stable/pdf/249… https://t.co/WduMlwZqf7

related posts