Jan Rączkowski was born in Siary near Gorlice to a peasant family. He never graduated from any schools. His career can be described as from rags to riches. He was quickly promoted to qualified worker and subsequently to master. In 1888, he took a job at the mine owned by Władysław Długosz. The mine went bankrupt and both men were hired by McGarvey, the founder of the machinery factory and refinery in Gorlice, who sent them to look for oil in Boryslav.
Over the first four years, the drillings were unsuccessful and McGarvey made a decision to cease exploration. However, Rączkowski did not give up and kept drilling. When the auger broke through 12m of rock at a depth of almost 1,000m, he struck top quality oil. This is how Jaś Rączkowski discovered the Borislav deposits. From then on, he had behind-the-scenes influence in the Galician-Carpathian Oil Association. No one knew how to drill below 1,000m as well as him and no one made better decisions when it came to malfunctions. He was a well-known and popular figure in Boryslav and was always eager to help others with advice or money.