This work focuses on the chronicles published in the mainstream press between 1901 and 1904 by Francisco Guimarães - a young black journalist who, in the following decades, would become one of the great names of Rio s carnival chronicle as Vagalume, the pseudonym under which he published one of the first studies on samba in 1933. It focuses in particular on two of his columns in the early years of the 20th century: Reportagem da Madrugada, published in the evening edition of Jornal do Brasil between April and July 1901; and Ecos Noturnos, published in the newspaper A Tribuna throughout 1904. By analyzing these two series, the aim is to show how Francisco Guimarães, by incorporating the demands and experiences of the workers of the period into his chronicles, helped to radically transform the press coverage of the world of work, by increasing the space dedicated to them in the various sheets. The result of this endeavor was both the creation of new spaces and columns in different newspapers and the success achieved by Vagalume in the Rio de Janeiro press of the First Republic.