On the basis of the results obtained in this investigation, the following conclusions were drawn: 1. Midlothian coal was 31.3 percent liquefied by hydrogenation at atmospheric pressure and 185°C after 72 hours of reaction in a tetralin vehicle and using stannous sulfide as a catalyst. 2. The liquid product of the hydrogenation of Midlothian coal consisted of approximately 50 percent light oil boiling below 200°C., 20 percent middle oil, boiling from 205°C. to 235°C., and 30 percent heavy oil or tar residue. 3. The light oil fraction of the hydrogenated product of Midlothian coal consisted of 5 to 10 percent each of olefins and saturated hydrocarbons, with the remainder being aromatic compounds. 4. The rate of liquefaction of Midlothian coal by hydrogenation researched a nearly constant value of 0.41 grams of liquid product produced per 100 grams of coal per hour after 24 hours of reaction. 5. During the first 24 hours period of hydrogenation, the volatile matter content of the carbonaceous residue increased by 5.0 percent after which the volatile matter decreased by 6.2 percent during the following 48 hour period. 6. During the hydrogenation reaction of 72 hours the fixed carbon content of the coal was reduced by 18 percent. 7. During the latter 48 hours period of reaction, 65 percent of the liquefaction was from the volatile matter constituents and 35 percent of the liquidation was from the fixed carbon components. / M.S.