The plant railroad also connected with the Catasauqua and Fogelsville and the Lehigh Valley Railroad at West Catasauqua, allowing it to receive ore and ship iron. Under the leadership of the Thomases, father and son, Thomas Iron produced record quantities of iron, and was looked upon as an exemplar of the iron industry. New furnaces were built at Hokendauqua: No. 3 was blown in on July 18, 1862 and No. 4 on April 29, 1863. On December 26, 1866, Samuel Thomas and other officials of Thomas Iron chartered the Lock Ridge Iron Company, which began building two furnaces at Alburtis in 1867. The first furnace was placed in blast on March 18, 1868. Lock Ridge Iron was bought by Thomas Iron on May 1, 1869, and the second furnace placed in blast on July 9, 1869. This facility had its own small plant railroad, which connected with the East Pennsylvania Railroad (later the Reading) and the Catasauqua and Fogelsville. Two more furnaces were built at Hokendauqua after the Civil War, No. 5 blown in on September 15, 1873 and No. 6 on January 19, 1874. The two Lock Ridge furnaces were later renumbered No. 7 and No. 8. After 1874, the company did not add any further furnaces at Hokendauqua. However, it purchased the Keystone Furnace from D. Runkle Company in early 1882 and the Saucon Iron Company in Hellertown, Pennsylvania on December 13, 1884, renaming its two furnaces No. 10 and No. 11. It leased the Lucy Furnace from 1886 to 1887. In 1881, a cinder notch was added to No. 8 furnace at Lock Ridge, an innovation which allowed removal of slag from the furnace during the blast. The operators initially struggled with fine-dirt problems after the change, and it was only eliminated when the furnace burnt out part of the lining. The furnace was re-lined to the new geometry and found to be much more efficient, and No. 7 and No. 2 furnaces were remodeled in the same fashion at the end of 1881. The other furnaces of the company were remodeled as they came out of blast. In 1882, Thomas Iron took over the Ironton Railroad. During the 1890s, as the local limonite industry declined and railroad transportation improved, Thomas Iron switched from using local ore to hematite from Michigan or overseas.