WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.

<TABLE> <S> <C>

<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE BALANCE
SHEET AT DECEMBER 31, 1998 AND THE STATEMENT OF OPERATIONS FOR THE TWELVE MONTHS
ENDED DECEMBER 31, 1998 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH
FINANCIAL STATEMENTS INCLUDED AS PART OF ITS ANNUAL REPORT ON FORM 10-K FOR THE
PERIOD DECEMBER 31, 1998.
</LEGEND>
       
<S>                             <C>
<PERIOD-TYPE>                   12-MOS
<FISCAL-YEAR-END>                          DEC-31-1998
<PERIOD-START>                             JAN-01-1998
<PERIOD-END>                               DEC-31-1998
<CASH>                                       1,858,833
<SECURITIES>                                         0
<RECEIVABLES>                                  830,947
<ALLOWANCES>                                         0
<INVENTORY>                                          0
<CURRENT-ASSETS>                             2,689,780
<PP&E>                                      52,861,434
<DEPRECIATION>                              16,622,403
<TOTAL-ASSETS>                              38,928,811
<CURRENT-LIABILITIES>                                0
<BONDS>                                              0
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                             0
<OTHER-SE>                                  38,928,811
<TOTAL-LIABILITY-AND-EQUITY>                38,928,811
<SALES>                                              0
<TOTAL-REVENUES>                             4,826,207
<CGS>                                                0
<TOTAL-COSTS>                                3,207,587
<OTHER-EXPENSES>                                     0
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                                   0
<INCOME-PRETAX>                                      0
<INCOME-TAX>                                         0
<INCOME-CONTINUING>                                  0
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                 1,740,032
<EPS-PRIMARY>                                        0
<EPS-DILUTED>                                        0
        
[ARTICLE] 5
[LEGEND]
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE BALANCE
SHEET AT SEPTEMBER 30, 1998 (UNAUDITED) AND THE STATEMENT OF OPERATIONS FOR THE
QUARTERLY PERIOD ENDED SEPTEMBER 30, 1998 (UNAUDITED) AND IS QUALIFIED IN ITS
ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS INCLUDED AS PART OF ITS
QUARTERLY REPORT ON FORM 10-Q FOR THE PERIOD SEPTEMBER 30, 1998.
[/LEGEND]
       
<S>                             <C>
[PERIOD-TYPE]                   9-MOS
[FISCAL-YEAR-END]                          DEC-31-1998
[PERIOD-START]                             JAN-01-1998
[PERIOD-END]                               SEP-30-1998
[CASH]                                       1,712,372
[SECURITIES]                                         0
[RECEIVABLES]                                1,010,405
[ALLOWANCES]                                         0
[INVENTORY]                                          0
[CURRENT-ASSETS]                             2,722,777
[PP&E]                                      52,922,940
[DEPRECIATION]                              15,872,003
[TOTAL-ASSETS]                              39,773,714
[CURRENT-LIABILITIES]                                0
[BONDS]                                              0
[PREFERRED-MANDATORY]                                0
[PREFERRED]                                          0
[COMMON]                                             0
[OTHER-SE]                                  39,773,714
[TOTAL-LIABILITY-AND-EQUITY]                39,773,714
[SALES]                                              0
[TOTAL-REVENUES]                             3,742,036
[CGS]                                                0
[TOTAL-COSTS]                                2,401,972
[OTHER-EXPENSES]                                     0
[LOSS-PROVISION]                                     0
[INTEREST-EXPENSE]                                   0
[INCOME-PRETAX]                                      0
[INCOME-TAX]                                         0
[INCOME-CONTINUING]                                  0
[DISCONTINUED]                                       0
[EXTRAORDINARY]                                      0
[CHANGES]                                            0
[NET-INCOME]                                 1,433,096
[EPS-PRIMARY]                                        0
[EPS-DILUTED]                                        0
        
[ARTICLE] 5
[LEGEND]
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE BALANCE
SHEET AT JUNE 30, 1998 (UNAUDITED) AND THE STATEMENT OF OPERATIONS FOR THE
QUARTERLY PERIOD ENDED JUNE 30, 1998 (UNAUDITED) AND IS QUALIFIED IN ITS
ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS INCLUDED AS PART OF ITS
QUARTERLY REPORT ON FORM 10-Q FOR THE PERIOD JUNE 30, 1998.
[/LEGEND]
       
<S>                             <C>
[PERIOD-TYPE]                   6-MOS
[FISCAL-YEAR-END]                          DEC-31-1998
[PERIOD-START]                             JAN-01-1998
[PERIOD-END]                               JUN-30-1998
[CASH]                                       1,839,760
[SECURITIES]                                         0
[RECEIVABLES]                                1,014,904
[ALLOWANCES]                                         0
[INVENTORY]                                          0
[CURRENT-ASSETS]                             2,854,664
[PP&E]                                      52,984,438
[DEPRECIATION]                              15,119,939
[TOTAL-ASSETS]                              40,719,292
[CURRENT-LIABILITIES]                                0
[BONDS]                                              0
[PREFERRED-MANDATORY]                                0
[PREFERRED]                                          0
[COMMON]                                             0
[OTHER-SE]                                  40,719,292
[TOTAL-LIABILITY-AND-EQUITY]                40,719,292
[SALES]                                              0
[TOTAL-REVENUES]                             2,655,403
[CGS]                                                0
[TOTAL-COSTS]                                1,602,399
[OTHER-EXPENSES]                                     0
[LOSS-PROVISION]                                     0
[INTEREST-EXPENSE]                                   0
[INCOME-PRETAX]                                      0
[INCOME-TAX]                                         0
[INCOME-CONTINUING]                                  0
[DISCONTINUED]                                       0
[EXTRAORDINARY]                                      0
[CHANGES]                                            0
[NET-INCOME]                                 1,122,121
[EPS-PRIMARY]                                        0
[EPS-DILUTED]                                        0
        
[ARTICLE] 5
[LEGEND]
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE BALANCE
SHEET AT MARCH 31, 1998 (UNAUDITED) AND THE STATEMENT OF OPERATIONS FOR THE
QUARTERLY PERIOD ENDED MARCH 31, 1998 (UNAUDITED) AND IS QUALIFIED IN ITS
ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS INCLUDED AS PART OF ITS
QUARTERLY REPORT ON FORM 10-Q FOR THE PERIOD MARCH 31, 1998.
[/LEGEND]
       
<S>                             <C>
[PERIOD-TYPE]                   3-MOS
[FISCAL-YEAR-END]                          DEC-31-1998
[PERIOD-START]                             JAN-01-1998
[PERIOD-END]                               MAR-31-1998
[CASH]                                       1,623,157
[SECURITIES]                                         0
[RECEIVABLES]                                1,103,093
[ALLOWANCES]                                         0
[INVENTORY]                                          0
[CURRENT-ASSETS]                             2,726,250
[PP&E]                                      53,024,536
[DEPRECIATION]                              14,359,942
[TOTAL-ASSETS]                              41,391,374
[CURRENT-LIABILITIES]                                0
[BONDS]                                              0
[PREFERRED-MANDATORY]                                0
[PREFERRED]                                          0
[COMMON]                                             0
[OTHER-SE]                                  41,391,374
[TOTAL-LIABILITY-AND-EQUITY]                41,391,374
[SALES]                                              0
[TOTAL-REVENUES]                             1,308,168
[CGS]                                                0
[TOTAL-COSTS]                                  807,236
[OTHER-EXPENSES]                                     0
[LOSS-PROVISION]                                     0
[INTEREST-EXPENSE]                                   0
[INCOME-PRETAX]                                      0
[INCOME-TAX]                                         0
[INCOME-CONTINUING]                                  0
[DISCONTINUED]                                       0
[EXTRAORDINARY]                                      0
[CHANGES]                                            0
[NET-INCOME]                                   537,650
[EPS-PRIMARY]                                        0
[EPS-DILUTED]                                        0
        
[ARTICLE] 5
[LEGEND]
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE BALANCE
SHEET AT DECEMBER 31, 1997 AND THE STATEMENT OF OPERATIONS FOR THE TWELVE MONTHS
ENDED DECEMBER 31, 1997 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH
FINANCIAL STATEMENTS INCLUDED AS PART OF ITS ANNUAL REPORT ON FORM 10-K FOR THE
PERIOD DECEMBER 31, 1997.
[/LEGEND]
       
<S>                             <C>
[PERIOD-TYPE]                   12-MOS
[FISCAL-YEAR-END]                          DEC-31-1997
[PERIOD-START]                             JAN-01-1997
[PERIOD-END]                               DEC-31-1997
[CASH]                                       1,576,719
[SECURITIES]                                         0
[RECEIVABLES]                                1,036,015
[ALLOWANCES]                                         0
[INVENTORY]                                          0
[CURRENT-ASSETS]                             2,612,734
[PP&E]                                      53,096,311
[DEPRECIATION]                              13,606,842
[TOTAL-ASSETS]                              42,110,227
[CURRENT-LIABILITIES]                                0
[BONDS]                                              0
[PREFERRED-MANDATORY]                                0
[PREFERRED]                                          0
[COMMON]                                             0
[OTHER-SE]                                  42,110,227
[TOTAL-LIABILITY-AND-EQUITY]                42,110,227
[SALES]                                              0
[TOTAL-REVENUES]                             5,372,706
[CGS]                                                0
[TOTAL-COSTS]                                3,227,927
[OTHER-EXPENSES]                                     0
[LOSS-PROVISION]                                     0
[INTEREST-EXPENSE]                                   0
[INCOME-PRETAX]                                      0
[INCOME-TAX]                                         0
[INCOME-CONTINUING]                                  0
[DISCONTINUED]                                       0
[EXTRAORDINARY]                                      0
[CHANGES]                                            0
[NET-INCOME]                                 2,285,497
[EPS-PRIMARY]                                        0
[EPS-DILUTED]                                        0
        
[ARTICLE] 5
[LEGEND]
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE BALANCE
SHEET AT MARCH 31, 1997, JUNE 30, 1997 AND SEPTEMBER 30, 1997 (UNAUDITED) AND
THE STATEMENT OF OPERATIONS FOR THE QUARTERLY PERIOD ENDED MARCH 31, 1997,
JUNE 30, 1997 AND SEPTEMBER 30, 1997 (UNAUDITED) AND IS QUALIFIED IN ITS
ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS INCLUDED AS PART OF ITS
QUARTERLY REPORT ON FORM 10-Q FOR THE PERIOD MARCH 31, 1997, JUNE 30, 1997 AND
SEPTEMBER 30, 1997.
[/LEGEND]
       
<S>                             <C>                     <C>                     <C>
[PERIOD-TYPE]                   3-MOS                   6-MOS                   9-MOS
[FISCAL-YEAR-END]                          DEC-31-1997             DEC-31-1997             DEC-31-1997
[PERIOD-START]                             JAN-01-1997             JAN-01-1997             JAN-01-1997
[PERIOD-END]                               MAR-31-1997             JUN-30-1997             SEP-30-1997
[CASH]                                       1,109,967               1,215,001               1,267,674
[SECURITIES]                                         0                       0                       0
[RECEIVABLES]                                1,160,480               1,052,809               1,162,767
[ALLOWANCES]                                         0                       0                       0
[INVENTORY]                                          0                       0                       0
[CURRENT-ASSETS]                             2,270,447               2,267,810               2,430,441
[PP&E]                                      53,173,480              53,106,373              53,131,844
[DEPRECIATION]                              11,331,881              12,091,152              12,843,837
[TOTAL-ASSETS]                              44,478,657              43,580,270              42,946,315
[CURRENT-LIABILITIES]                                0                       0                       0
[BONDS]                                              0                       0                       0
[PREFERRED-MANDATORY]                                0                       0                       0
[PREFERRED]                                          0                       0                       0
[COMMON]                                             0                       0                       0
[OTHER-SE]                                  44,478,657              43,580,270              42,946,315
[TOTAL-LIABILITY-AND-EQUITY]                44,478,657              43,580,270              42,946,315
[SALES]                                              0                       0                       0
[TOTAL-REVENUES]                             1,220,351               2,498,145               3,953,363
[CGS]                                                0                       0                       0
[TOTAL-COSTS]                                  866,839               1,741,075               2,600,417
[OTHER-EXPENSES]                                     0                       0                       0
[LOSS-PROVISION]                                     0                       0                       0
[INTEREST-EXPENSE]                                   0                       0                       0
[INCOME-PRETAX]                                      0                       0                       0
[INCOME-TAX]                                         0                       0                       0
[INCOME-CONTINUING]                                  0                       0                       0
[DISCONTINUED]                                       0                       0                       0
[EXTRAORDINARY]                                      0                       0                       0
[CHANGES]                                            0                       0                       0
[NET-INCOME]                                   407,871                 844,654               1,467,252
[EPS-PRIMARY]                                        0                       0                       0
[EPS-DILUTED]                                        0                       0                       0
        
[ARTICLE] 5
[LEGEND]
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE BALANCE
SHEET AT DECEMBER 31, 1996 AND THE STATEMENT OF OPERATIONS FOR THE TWELVE MONTHS
ENDED DECEMBER 31, 1996 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH
FINANCIAL STATEMENTS INCLUDED AS PART OF ITS ANNUAL REPORT ON FORM 10-K FOR THE
PERIOD DECEMBER 31, 1996.
[/LEGEND]
       
<S>                             <C>
[PERIOD-TYPE]                   12-MOS
[FISCAL-YEAR-END]                          DEC-31-1996
[PERIOD-START]                             JAN-01-1996
[PERIOD-END]                               DEC-31-1996
[CASH]                                       1,730,504
[SECURITIES]                                         0
[RECEIVABLES]                                1,173,515
[ALLOWANCES]                                         0
[INVENTORY]                                          0
[CURRENT-ASSETS]                             2,904,019
[PP&E]                                      52,798,896
[DEPRECIATION]                              10,575,957
[TOTAL-ASSETS]                              45,562,941
[CURRENT-LIABILITIES]                                0
[BONDS]                                              0
[PREFERRED-MANDATORY]                                0
[PREFERRED]                                          0
[COMMON]                                             0
[OTHER-SE]                                  45,562,941
[TOTAL-LIABILITY-AND-EQUITY]                45,562,941
[SALES]                                              0
[TOTAL-REVENUES]                             6,755,171
[CGS]                                                0
[TOTAL-COSTS]                                3,454,634
[OTHER-EXPENSES]                                     0
[LOSS-PROVISION]                                     0
[INTEREST-EXPENSE]                                   0
[INCOME-PRETAX]                                      0
[INCOME-TAX]                                         0
[INCOME-CONTINUING]                                  0
[DISCONTINUED]                                       0
[EXTRAORDINARY]                                      0
[CHANGES]                                            0
[NET-INCOME]                                 3,495,007
[EPS-PRIMARY]                                        0
[EPS-DILUTED]                                        0
        
[ARTICLE] 5
[LEGEND]
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE BALANCE
SHEET AT MARCH 31, 1996, JUNE 30, 1996 AND SEPTEMBER 30, 1996 (UNAUDITED) AND
THE STATEMENT OF OPERATIONS FOR THE QUARTERLY PERIOD ENDED MARCH 31, 1996,
JUNE 30, 1996 AND SEPTEMBER 30, 1996 (UNAUDITED) AND IS QUALIFIED IN ITS
ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS INCLUDED AS PART OF ITS
QUARTERLY REPORT ON FORM 10-Q FOR THE PERIOD MARCH 31, 1996, JUNE 30, 1996
AND SEPTEMBER 30, 1996.
[/LEGEND]
       
<S>                             <C>                     <C>                     <C>
[PERIOD-TYPE]                   3-MOS                   6-MOS                   9-MOS
[FISCAL-YEAR-END]                          DEC-31-1996             DEC-31-1996             DEC-31-1996
[PERIOD-START]                             JAN-01-1996             JAN-01-1996             JAN-01-1996
[PERIOD-END]                               MAR-31-1996             JUN-30-1996             SEP-30-1996
[CASH]                                       1,628,325               1,427,492               1,594,839
[SECURITIES]                                         0                       0                       0
[RECEIVABLES]                                1,163,029               1,308,851               1,537,736
[ALLOWANCES]                                         0                       0                       0
[INVENTORY]                                          0                       0                       0
[CURRENT-ASSETS]                            22,791,354               2,736,343               2,748,575
[PP&E]                                      53,027,465              53,007,643              52,928,400
[DEPRECIATION]                               8,310,326               9,073,702               9,832,173
[TOTAL-ASSETS]                              48,152,591              47,245,010              46,350,157
[CURRENT-LIABILITIES]                          274,040                 182,040                  91,040
[BONDS]                                              0                       0                       0
[PREFERRED-MANDATORY]                                0                       0                       0
[PREFERRED]                                          0                       0                       0
[COMMON]                                             0                       0                       0
[OTHER-SE]                                  47,878,551              47,062,970              46,259,117
[TOTAL-LIABILITY-AND-EQUITY]                48,152,591              47,245,010              46,350,157
[SALES]                                              0                       0                       0
[TOTAL-REVENUES]                             1,770,578               3,566,930               5,170,080
[CGS]                                                0                       0                       0
[TOTAL-COSTS]                                  866,190               1,730,751               2,598,158
[OTHER-EXPENSES]                                     0                       0                       0
[LOSS-PROVISION]                                     0                       0                       0
[INTEREST-EXPENSE]                                   0                       0                       0
[INCOME-PRETAX]                                      0                       0                       0
[INCOME-TAX]                                         0                       0                       0
[INCOME-CONTINUING]                                  0                       0                       0
[DISCONTINUED]                                       0                       0                       0
[EXTRAORDINARY]                                      0                       0                       0
[CHANGES]                                            0                       0                       0
[NET-INCOME]                                   967,659               1,932,192               2,669,028
[EPS-PRIMARY]                                        0                       0                       0
[EPS-DILUTED]                                        0                       0                       0
        

</TABLE>