Device for measuring lateral spreading of electrons
1907-1908
Brass release device for bell jar
1800-1899
Electrical device for solving algebraic equations
High frequency (violet ray) device
1920-1955
A device for placing rings on the feet of racing pigeons
Electrostatic indicating device consisting of two glass arms freely pivoted on a lightweight stand
1780-1798
Lightning conductor earth: Cast iron self-watering device with grid
1918