August Martin (1808-1892) from Dachwig (Thuringia) worked in Riga from 1837. He is known to have built about 67 church and 19 school organs in the Baltics, Russia, and Poland during 1840-1885. His largest instrument, originally built for the Old Church of St Gertrude in Riga (1867-1876, III/P/31), was removed in 1906 to the New Church of St Gertrude in that city. His son Emil Martin (1848-1922), who worked for four years under Friedrich Ladegast, installed the instrument in the Catholic church of St Jacob in Riga (1913, II/P/35, Opus 322). Friedrich Weissenborn from Thuringia, who lived in Riga, Krustpils, and Jekabpils (Jakobstadt), produced 85 organs in Latvia and Lithuania during the period 1865-1894.

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