169 years ago, surgery became just a little more tolerable.

According to Mass Moments, a Boston dentist named William Morton entered Dr. John Warren’s Massachusetts General Hospital operating room with a glass apparatus on this day in 1846. It had an inhaler and a chamber with an ether-soaked sponge inside of it. Warren’s patient was rendered unconscious after breathing from the contraption and, upon waking up, claimed that he’d felt no pain during a procedure in which a tumor was removed from his jaw.

And the rest was surgical history.

A London newspaper that ran shortly after the historic surgery read, “WE HAVE CONQUERED PAIN.” And, considering the other methods of suppressing pain at the time, that headline wasn’t too much of a stretch. Before Morton brought his ether chamber to Warren’s operation, opium and alcohol were the only analgesics regularly used and had to be delivered to patients in near-lethal doses to even be effective.

The use of ether was such a dramatic breakthrough in the medical world that a 40-foot tall monument dedicated to Morton was proposed just two years later. The statue was commissioned by a Boston businessman who wanted to “commemorate the discovery that the inhaling of ether causes insensibility to pain. First proved at the Mass. General Hospital in Boston.”

The monument still stands today in the Boston Common.