Many, man , many house “fires” were caused by ….. tipped over and broken kerosene lamps ….. thus that “ring” wall mount bracket was a kinda “safety feature”.
Yeah, matter of fact, whale oil lamps put candle stands out of business, those 3 leg stands for candles just didn't cut it for oil or later kerosene lamps & so 4 leg "light stands" were born. They are referred to as "work stands" today and most are incredibly affordable for beginning furniture collectors and very plentiful as well, millions were built throughout the 19th century to safely support oil lamps. It makes sense that they would have sturdy wall brackets to raise and support these lamps, especially in hallways for example.