Sulfur was not "added" to the periodic table in the sense of a new discovery. It has been known and used by humans for millennia.

Here's the breakdown:

* Ancient Times: Sulfur was known and used in ancient civilizations, particularly for its medicinal and alchemical properties.

* 18th Century: Antoine Lavoisier, a French chemist, recognized sulfur as an element in 1777.

* 19th Century: Dmitri Mendeleev, a Russian chemist, developed the periodic table in 1869, placing sulfur in its appropriate position based on its properties.

So, while sulfur has been known for a long time, it was formally recognized as an element in the 18th century and placed in the periodic table in the 19th century.