3 facts
Roman concrete, particularly that used for harbors, has endured for over 2,000 years, outperforming many modern mixtures. Its durability is attributed to a unique blend of volcanic ash, lime, and seawater, which creates a robust, self-healing material that resists erosion.
The original Slinky toy, invented by Richard James in 1943, contains 80 feet of steel wire. Its unique design allows it to "walk" down stairs and perform various mesmerizing tricks.
Due to thermal expansion, the iron structure of the tower expands when heated by the sun, causing it to grow in height. Conversely, it contracts in colder temperatures, returning to its original size, a testament to the properties of its material.