<ARTICLE> 5 <PERIOD-TYPE> 6-MOS <FISCAL-YEAR-END> DEC-31-1997 <PERIOD-START> JAN-01-1997 <PERIOD-END> JUN-30-1997 <CASH> 2,550,324 <SECURITIES> 590,090 <RECEIVABLES> 1,060,061 <ALLOWANCES> 10,000 <INVENTORY> 0 <CURRENT-ASSETS> 4,190,475 <PP&E> 20,277,394 <DEPRECIATION> 18,016,364 <TOTAL-ASSETS> 6,451,505 <CURRENT-LIABILITIES> 361,823 <BONDS> 191,201 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <COMMON> 0 <OTHER-SE> 5,898,481 <TOTAL-LIABILITY-AND-EQUITY> 6,451,505 <SALES> 0 <TOTAL-REVENUES> 1,782,522 <CGS> 0 <TOTAL-COSTS> 0 <OTHER-EXPENSES> 1,246,052 <LOSS-PROVISION> 0 <INTEREST-EXPENSE> 20,723 <INCOME-PRETAX> 515,747 <INCOME-TAX> 0 <INCOME-CONTINUING> 515,747 <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> 515,747 <EPS-PRIMARY> 0 <EPS-DILUTED> 0