The mining jurisdiction and the tithes that had been granted in 1235 to the Brunswick Welfs and enfeoffed in 1296 to the knights of the Gowische were taken over by the Sechsmannen in 1356 and then from them to the town council. In 1359 the Goslar Mining Law was passed. As a consequence of this development, the council sought in 1360 to resolve the drainage issue in order to reactivate the mine that had now almost come to a standstill. In 1407, 1418 and 1432, the council tried, in association with foreign investors and various master miners, to drain the pits. In the years 1453-1456 Claus von Gotha achieved partial success with the Heinzenkunst a water wheel designed to lift and empty a chain of water buckets. By 1471 mining had recovered to such an extent that the council introduced new charges for the trades and ended up buying all the shares from the mine's owner. From 1478 the smelting of metals was also facilitated by the new Seigerverfahren dressing process. Attempts by the dukes of Brunswick to redeem the pledge for the Rammelsberg again redeem were prevented by the town in 1477 and 1484. Goslar experienced a major boom from the proceeds of the mine and smelters. By 1511 the council was able to gain sole ownership of all mines at Rammelsberg.