"The distillation studies at the Rifle Station of the US Bureau of Mines were made with the following principal purposes: 1. To establish on a semi-plant scale the suitability of this specific type of distillation unit for the processing of lignite tar produced by the Parry process in a commercial carbonizer at the Rockdale plant of the Aluminum Company of America. 2. To establish the yields and qualities, of the distillates and residues produced in various modes of operation of the distillation unit; and 3. To produce pitches in sufficient quantities for plant scale evaluation in prebaked electrodes for aluminum manufacture and to produce distillates in sufficient quantities for further processing in one of Koppers tar plants. The purpose of this report is to summarize evaluation data which has been obtained since the first report was issued on September 27, 1954."