UNITED STATES

                       SECURITIES AND EXCHANGE COMMISSION

                              Washington, DC 20549

                                    Form 13F

                               FORM 13F COVER PAGE

Report for the Calendar Year or Quarter Ended:   September 30, 2004

Institutional Investment Manager Filing this Report:
Name:    General American Investors Company, Inc.
Address: 450 Lexington Avenue, Suite 3300
         New York, NY  10017

13F File Number: 28-461

The institutional  investment  manager filing this report and the person by whom
it is signed hereby  represent  that the person signing the report is authorized
to  submit  it,  that all  information  contained  herein is true,  correct  and
complete,  and  that it is  understood  that  all  required  items,  statements,
schedules, lists, and tables, are considered integral parts of this form.

Person Signing this Report:
Name:  Eugene L. DeStaebler, Jr.
Title: Vice-President, Administration
Phone: 212-916-8400
Signature, Place and Date of Signing:
     Eugene L. DeStaebler, Jr.     New York, NY      October 26, 2004

Report Type  (Check only one.):

[x]       13F HOLDINGS REPORT
[ ]       13F NOTICE
[ ]       13F COMBINATION REPORT

List of Other Managers Reporting for this Manager:
    NONE

I am signing this report as required by the Securities Exchange Act of 1934.



                     FORM 13F SUMMARY PAGE

Report Summary:
Number of Other Included Managers:      0
Form 13F Information Table Entry Total: 58
Form 13F Information Table Value Total: $1,049,614,286




      NAME OF ISSUER         TITLE    CUSIP          FAIR      SHARES OR          INVEST. DISC.    OTHER      VOTING AUTHORITY
                              OF      NUMBER        MARKET     PRINCIPAL  SH/               SHARED  MGRS.
                             CLASS                   VALUE      AMOUNT    PRN    SOLE SHARED OTHER        SOLE     SHARED   NONE
                                                                                 (A)   (B)   (C)          (A)       (B)      (C)
 ----------------------------------------------------------------------------------------------------------------------------------
                                                                                    
 Adams Express Company      COMMON 006212104       1,193,061      94,090 N  X                        94,090                        
 American International Gro COMMON 026874107      18,017,350     265,000 N  X                       265,000                        
 Alkermes, Inc.             COMMON 01642T108       3,923,600     340,000 N  X                       340,000                        
 American Tower Corporation COMMON 029912201       8,442,500     550,000 N  X                       550,000                        
 Annuity and Life Re (Holdi COMMON G03910109         250,000     625,000 N  X                       625,000                        
 Apache Corporation         COMMON 037411105      19,542,900     390,000 N  X                       390,000                        
 Bank of America Corporatio COMMON 060505104      15,945,440     368,000 N  X                       368,000                        
 Baxter International Inc.  COMMON 071813109      26,532,000     825,000 N  X                       825,000                        
 Bancroft Convertible Fund  COMMON 059695106         386,642      21,070 N  X                        21,070                        
 Biogen Idec Inc.           COMMON 09062X103      15,292,500     250,000 N  X                       250,000                        
 Bristol-Myers Squibb Compa COMMON 110122108       7,101,000     300,000 N  X                       300,000                        
 Berkshire Hathaway Inc.    COMMON 084670108      25,995,000         300 N  X                           300                        
 Brooks Automation, Inc.    COMMON 114340102       6,954,725     491,500 N  X                       491,500                        
 Central Securities Corpora COMMON 155123102       2,515,140     113,040 N  X                       113,040                        
 CIENA Corporation          COMMON 171779101       1,089,000     550,000 N  X                       550,000                        
 Costco Wholesale Corporati COMMON 22160K105      29,057,000     700,000 N  X                       700,000                        
 Cox Communications, Inc. - COMMON 224044107      20,540,600     620,000 N  X                       620,000                        
 Cisco Systems, Inc.        COMMON 17275R102      16,290,000     900,000 N  X                       900,000                        
 CEMEX, S.A. de C.V.        COMMON 151290889      26,733,000     950,000 N  X                       950,000                        
 Diageo plc                 COMMON 25243Q205      17,650,500     350,000 N  X                       350,000                        
 Genentech, Inc.            COMMON 368710406      29,355,200     560,000 N  X                       560,000                        
 Devon Energy Corporation   COMMON 25179M103      56,808,000     800,000 N  X                       800,000                        
 EMC Corporation            COMMON 268648102       3,462,000     300,000 N  X                       300,000                        
 EMCORE Corporation         COMMON 290846104         388,090     197,000 N  X                       197,000                        
 El Paso Corporation 0%     CONV C 28336LAC3      11,475,000  22,500,000 N  X                    22,500,000                        
 Ethan Allen Interiors Inc. COMMON 297602104       9,556,250     275,000 N  X                       275,000                        
 Golden West Financial      COMMON 381317106      36,058,750     325,000 N  X                       325,000                        
 Genaera Corporation        COMMON 36867G100       1,055,700     270,000 N  X                       270,000                        
 Genta Incorporated         COMMON 37245M207       1,008,750     375,000 N  X                       375,000                        
 Halliburton Company        COMMON 406216101      20,214,000     600,000 N  X                       600,000                        
 The Home Depot, Inc.       COMMON 437076102      75,264,000   1,920,000 N  X                     1,920,000                        
 Juniper Networks, Inc.     COMMON 48203R104       3,540,000     150,000 N  X                       150,000                        
 Lamar Advertising Company  COMMON 512815101      20,805,000     500,000 N  X                       500,000                        
 Medtronic, Inc.            COMMON 585055106      23,355,000     450,000 N  X                       450,000                        
 MedImmune, Inc.            COMMON 584699102      10,783,500     455,000 N  X                       455,000                        
 MetLife, Inc.              COMMON 59156R108      16,812,750     435,000 N  X                       435,000                        
 MFA Mortgage Investments,  COMMON 55272X102       7,828,500     850,000 N  X                       850,000                        
 Millennium Pharmaceuticals COMMON 599902103       1,640,400     120,000 N  X                       120,000                        
 Molex Incorporated Class A COMMON 608554200      18,818,800     715,000 N  X                       715,000                        
 Montpelier Re Holdings Ltd COMMON G62185106       6,419,000     175,000 N  X                       175,000                        
 Microsoft Corporation      COMMON 594918104      42,166,250   1,525,000 N  X                     1,525,000                        
 M&T Bank Corporation       COMMON 55261F104      31,581,000     330,000 N  X                       330,000                        
 Annaly Mortgage Management COMMON 035710409      13,275,750     775,000 N  X                       775,000                        
 NetIQ Corporation          COMMON 64115P102       6,666,100     623,000 N  X                       623,000                        
 PepsiCo, Inc.              COMMON 713448108       7,297,500     150,000 N  X                       150,000                        
 Pfizer Inc                 COMMON 717081103      40,545,000   1,325,000 N  X                     1,325,000                        
 PartnerRe Ltd.             COMMON G6852T105      27,345,000     500,000 N  X                       500,000                        
 Everest Re Group, Ltd.     COMMON G3223R108      48,314,500     650,000 N  X                       650,000                        
 Reinsurance Group of Ameri COMMON 759351109      18,334,000     445,000 N  X                       445,000                        
 Republic Services, Inc.    COMMON 760759100      34,968,000   1,175,000 N  X                     1,175,000                        
 Royce Value Trust          COMMON 780910105       1,812,580     100,867 N  X                       100,867                        
 SunTrust Banks, Inc.       COMMON 867914103      14,434,050     205,000 N  X                       205,000                        
 The TJX Companies, Inc.    COMMON 872540109      55,100,000   2,500,000 N  X                     2,500,000                        
 Total S.A. ADR             COMMON 89151E109      25,235,990     247,000 N  X                       247,000                        
 Transatlantic Holdings, In COMMON 893521104      15,285,938     281,250 N  X                       281,250                        
 Unocal Corporation         COMMON 915289102       8,600,000     200,000 N  X                       200,000                        
 VeriSign, Inc.             COMMON 92343E102       4,641,980     233,500 N  X                       233,500                        
 Wal-Mart Stores, Inc.      COMMON 931142103      35,910,000     675,000 N  X                       675,000