How much weight could William Sturgeon’s 1820s electromagnet lift?

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electromagnet Figure 1: Elements of a solenoid

In 1825, William Sturgeon exhibited his first electromagnet, which weighed 7 ounces (200 grams). Using the current from a single cell, this device was capable of supporting 9 pounds (4 kilograms) of iron.1

Sturgeon’s design, which involved wrapping 18 turns of bare copper wire around a U-shaped iron bar, demonstrated that the magnet could lift approximately 20 times its own weight. This achievement was a significant milestone in the development of electromagnetism, as it was the first electromagnet capable of supporting more than its own weight.21