Martinus Van Marum (1750-1837), a Dutch chemist, is known for his electrostatic machines (1784) and for the discovery of ozone produced by electrical sparks in the air. From these experiments, van Marum concluded that copper was the best material for lightning conductors while lead was the worst, and that the static and the galvanic forms of electricity are equal and have the same origin. He subjected oxygen to electrical discharges, and noted "the odor of electrical matter" and the accelerated oxidation of mercury (1785). Thus, van Marum reported the odor of ozone, but he failed to identify it as a unique form of oxygen.
Ozone and Van Marum's Electrostatic Generator (Lateral Science)