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                                                                     Exhibit 23A


                  [RALPH E. DAVIS ASSOCIATES, INC. LETTERHEAD]


                                January 24, 2000


CONSOLIDATED NATURAL GAS COMPANY
CNG Tower
625 Liberty Avenue
Pittsburgh, Pennsylvania 15222-3199


                       Report Covering Natural Gas Supply
                             And Owned Oil Reserves
                               December 31, 1999
                           --------------------------

Gentlemen:

     Consolidated Natural Gas Company, through its subsidiaries (collectively
Consolidated or the Company) is engaged in exploring for, developing, producing,
purchasing, gathering, transporting, storing and distributing natural gas,
together with by-product operations. The principal market area of the Company's
retail operations is in Ohio, Pennsylvania, Virginia and West Virginia. However,
one of the Company's subsidiaries, Virginia Natural Gas, Inc., with retail
operations in Virginia, will be sold or spun off within twelve months of the
consummation of the Company's pending merger with Dominion Resources, Inc.
Consolidated operates a regional interstate pipeline system that supplies
natural gas to affiliates, and to utilities and end-users in the Midwest,
Mid-Atlantic states and the Northeast. Exploration and production activities are
carried on primarily in the Appalachian area, the Gulf Coast area (including
offshore), the Mid-Continent area, the Permian Basin area, the Rocky Mountain
area and in Canada.

     From 1943 to 1993 Consolidated purchased gas from pipeline companies which
obtained their gas supply from fields in the Gulf Coast and Southwest. Since
1993, however, all remaining long-term gas purchase contracts with pipelines
have been replaced with firm transport contracts



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Consolidated Natural Gas Company                                January 24, 2000
                                                                          Page 2


as the result of Federal Energy Regulatory Commission (FERC) Order 636.
Consolidated purchases gas under contracts with producers and marketers, and
also purchases gas on the spot market. A substantial part of these gas supplies
are also obtained from fields in the Gulf Coast and Southwest. Since 1957
Consolidated has also been engaged in exploration and production of gas in
Louisiana and the Texas Gulf Coast, including offshore. During the twelve months
ended December 31, 1999 most of the gas produced and purchased by the Company
was obtained from the Southwest. All gas volumes herein are stated at a
measuring base of 14.73 pounds per square inch absolute.


                           APPALACHIAN AREA RESERVES

     Studies of the natural gas available from Appalachian gas fields lead us to
conclude that the Company may expect to obtain for a number of years a supply
from this area. The development which has occurred in this natural gas province
has resulted in extensive drilling of shallow formations in much of the area.
The entire sedimentary section has not been adequately tested in the Appalachian
area and there is the possibility that natural gas is present in commercial
quantities below the known producing formations. Consolidated has participated
in programs to test deeper formations. Consolidated has also found that reentry
into old wells has been beneficial in finding commercial quantities behind pipe.

     We estimate Consolidated's working interest proved reserves in the
Appalachian fields, as of December 31, 1999, to be 328 billion cubic feet
(including CNG Producing Company's Appalachian reserves) from company-owned
wells and 223 billion cubic feet from gas purchase wells, for a total of 551
billion cubic feet, exclusive of gas in storage reservoirs. Total additions to
the reserves controlled by the Company in the Appalachian fields have in the
past been substantial. It is possible that future exploration and development
will locate appreciable new reserves. In addition, subsidiary companies had
remaining working interest oil reserves estimated at 456,128 barrels (including
CNG Producing Company's Appalachian oil reserves) in the Appalachian area.
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Consolidated Natural Gas Company                                January 24, 2000
                                                                          Page 3


                             CNG PRODUCING COMPANY

     CNG Producing Company is Consolidated's primary exploration and production
subsidiary. As of December 31, 1999, the estimated proved working interest
reserves of CNG Producing Company are 1,309 billion cubic feet of gas and
59,662,520 barrels of crude oil and condensate. The foregoing totals include
approximately 1 billion cubic feet of gas and 8,137,917 barrels of heavy oil
reserves in Canada.

     In the United States, CNG Producing Company has proved reserves in 9 states
and the offshore area of the Gulf Coast. The majority of CNG Producing Company's
United States reserves are in the Gulf Coast (primarily offshore), the South
Texas area, the Appalachian area and the Rocky Mountain area. The estimated
proved reserves in the United States are 1,308 billion cubic feet of gas and
51,524,603 barrels of crude oil and condensate.

     The estimated Appalachian proved reserves as of December 31, 1999 for CNG
Producing Company, which are included in the total Appalachian reserves
disclosed earlier in this report, are 188 billion cubic feet of gas and 200,853
barrels of oil. In addition to the Appalachian area, CNG Producing Company
conducts exploration and development programs in other areas, including San Juan
Basin in New Mexico. The San Juan Basin has a history of oil and gas production
from conventional sources, but recent interest in the area stems from an
unconventional source of gas supply. This interest is the Fruitland Coal
formation, where CNG Producing Company and others are producing gas from the
coal beds. The estimated San Juan Basin proved reserves of CNG Producing Company
as of December 31, 1999 are 12 billion cubic feet.


                                 SOUTHWEST GAS

     Consolidated's subsidiaries have gas supply contracts with various gas
producing companies and marketing groups with remaining terms ranging from a few
months to as long as five years. Purchase entitlements under these contracts
total approximately 91 billion cubic feet, if all volumes are requested. This
estimate gives no consideration to the estimated volumes of spot market gas
which may be purchased in the future.
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Consolidated Natural Gas Company                                January 24, 2000
                                                                          Page 4


                                  GAS STORAGE

     The Company owns and operates 26 gas storage fields, five of which are
owned and operated jointly with other companies. One storage field is owned and
operated jointly with Texas Eastern Transmission Corporation (Texas Eastern),
one with Tennessee Gas Pipeline Company (Tennessee), one with Penn Fuel Gas,
Inc., one with both Tennessee and National Fuel Gas Supply Corporation, and
another  with both Texas Eastern and Transcontinental Gas Pipe Line Corporation.
Consolidated's net injected gas stored at December 31, 1999, was 430 billion
cubic feet (including 53 billion cubic feet or remaining non-recoverable native
gas, and 60 billion cubic feet of non-recoverable base gas.)

     The proximity of these storage fields to principal markets and their high
deliverability are important factors in enabling the Company to meet peak loads
and daily requirements during the heating season, and permit the gas purchased
to be taken relatively uniformly in summer and winter.

     There are additional depleted, or nearly depleted, gas fields in the
Appalachian area which can be converted to storage fields if needed.


                            POTENTIAL SUPPLY SOURCES

     In order to meet the demands for gas in its market area over the long-term
future, Consolidated may need additional supplies over those available from the
sources discussed above. Other potential sources of gas could come from reserves
in Alaska, Canada, and Mexico, liquefied natural gas from abroad, synthetic gas
from coal or other feed stock and additional coalbed methane.


                            SUMMARY AND CONCLUSIONS

     We have estimated proved working interest crude oil and condensate reserves
owned by Consolidated from sources in the United States and Canada at 59,917,815
barrels as of December 31, 1999 as follows:
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Consolidated Natural Gas Company                               January 24, 2000
                                                                         Page 5




                                                Stock Tank Barrels
                                                ------------------

Appalachian Field Reserves                            255,295
--------------------------


CNG Producing Company
---------------------

  Southwest                                        59,461,667

  Appalachian                                         200,853
                                                   ----------
          Sub Total                                59,662,520


TOTAL - OWNED OIL AND CONDENSATE RESERVES          59,917,815


We have estimated the gas reserves available to Consolidated from sources in
the United States and Canada at 2,193 billion cubic feet as of December 31,
1999 as follows:


                                                   Billion
                                                  Cubic Feet
                                                 at 14.73 psia
                                                 -------------

Appalachian Field Reserves
--------------------------

     Company-Owned Wells                              140
     Gas Purchase Contract Wells                      223
     Gas in Storage Reservoirs                        430
                                                    -----
          Sub-Total                                   793

CNG Producing Company Reserves
------------------------------
     Company-Owned Wells
          Southwest                                 1,121
          Appalachian                                 188
                                                    -----
               Sub-Total                            1,309

Gas Supply Contracts                                   91
--------------------

TOTAL - CONTROLLED GAS RESERVES                     2,193




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Consolidated Natural Gas Company                               January 24, 2000
                                                                         Page 6




     Consolidated's requirements for the twelve months ended December 31, 1999,
including sales of gas produced in Canada, were approximately 526 billion cubic
feet, compared to requirements of 452 billion cubic feet in 1998.

     Additional supplies are expected to become available from the Appalachian
area, the Gulf Coast and other areas and from company-owned reserves.

     Potential sources of supply include additional gas from Canada, Mexico and
Alaska, liquefied natural gas from abroad, gas from the reforming of liquid
hydrocarbons such as naphtha and oil, gas from coal gasification and coalbed
methane.

     The time at which these additional supplies will become available cannot
be definitely predicted. However, Consolidated is in a favorable position to
secure gas supplies from many directions, including its proven reserves, the
volume of gas in underground storage, the prospects for additional supplies
from its traditional supply areas, the several potential supply sources and the
Company's own program to augment its supply.



                              Yours very truly,

                              RALPH E. DAVIS ASSOCIATES, INC.

                              /s/ Thomas N. Sudderth
                              ------------------------------
                              Thomas N. Sudderth
                              President

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                  [RALPH E. DAVIS ASSOCIATES, INC. LETTERHEAD]




                                 March 7, 2000



                       CONSENT OF INDEPENDENT GEOLOGISTS


     We hereby consent to the use of our report dated January 24, 2000,
relating to the total gas supply and Company-owned oil and gas reserves of
Consolidated Natural Gas Company, to be filed as an Exhibit to Consolidated
Natural Gas Company's Annual Report on Form 10-K for the year ended December
31, 1999. We further consent to the filing hereof as an Exhibit to said Annual
Report on Form 10-K.

     We also consent to the incorporation by reference into the Registration
Statement on Form S-3 (No. 333-92765) of Consolidated Natural Gas Company, and
the prospectus made a part thereof, of our estimates of Company-owned oil and
gas reserves in the United States and Canada included in Consolidated Natural
Gas Company's Annual Report on Form 10-K for the year ended December 31, 1999.
We also consent to the reference to us under the heading "Experts" in such
Prospectus.



                                             /s/ Thomas N. Sudderth
                                             -----------------------------
                                             Thomas N. Sudderth