‘Unity: An Address Delivered at New Pythagoras Hall, New York, February 21, 1908’ by by Daniel De Leon. New York Labor News, 1908.
New York Labor News Company was the publishing house of the Socialist Labor Party and their paper The People. The People was the official paper of the Socialist Labor Party of America (SLP), established in New York City in 1891 as a weekly. The New York SLP, and The People, were dominated Daniel DeLeon and his supporters, the dominant ideological leader of the SLP from the 1890s until the time of his death. The People became a daily in 1900. It’s first editor was the French socialist Lucien Sanial who was quickly replaced by DeLeon who held the position until his death in 1914. Morris Hillquit and Henry Slobodin, future leaders of the Socialist Party of America were writers before their split from the SLP in 1899. For a while there were two SLPs and two Peoples, requiring a legal case to determine ownership. Eventual the anti-DeLeonist produced what would become the New York Call and became the Social Democratic, later Socialist, Party. The DeLeonist The People continued publishing until 2008.
PDF of pamphlet: http://palmm.digital.flvc.org/islandora/object/ucf%3A4955/datastream/OBJ/download/Unity__An_address_delivered_by_Daniel_De_Leon_at_New_Pythagoras_Hall__New_York__February_21__1908.pdf