Merklin retired in 1898 and died in Nancy at the age of 86. In his lifetime he had built, restored, or repaired over 400 organs. Many of the organs he built in France are now classified as historical monuments by the French Ministry of Culture.For the complete list, see Ministère de la Culture (France). Search: "Merklin", Base Palissy . His grandson, Charles-Marie Michel was a promising organist and student of Louis Vierne, but died in 1897 at the age of 20. His nephew, Albert Merklin (1892 – 1925), became an organ builder. He went to Madrid at the outbreak of World War I to establish a firm there and wrote a treatise on the history and construction of Spanish organs published in 1924.Albert Merklin's 1924 treatise, Organología: Exposición científica y gráfica del órgano en todos sus elementos y recursos antiguos y modernos, was republished in 1939 by Rheingold-Verlag in an expanded German version, Aus Spaniens altem Orgelbau.
