Various ancestors living in Blackrod worked as Calico Printers or Block Printers. According to Wikipedia there was a calico printing works there, though no descriptions of this can be found.
In the 1848 map there is a Horwich Vale Print Works between Blackrod and Horwich, by the River Douglas, founded in 1799 to print cloth using machines and handblocks (according to Wikipedia). This closed in 1860 due to changes in the water supply from Rivington (see Rivington Lakes for more information). This could be where the ancestors worked.
However James Crankshaw continued to work as a Calico Printer past 1860 until his death in 1873 so printing must have been going on somewhere else in Blackrod.
See Wikipedia for more information about Calico Printing and Block Printing.
Norman And Marian Barton Family Tree 