Mount Desert Rock (Maine)
Historical Light List Characteristics
| 1839 | F W. W20. | USLHE Light List (US): 20 |
| 1849 | F W. W15. | |
| 1858 | F W. W14. | LHB Light List (US): 12 |
| 1860 | LHB Light List (US): 9 | |
| 1865-1866 | LHB Light List (All Coasts): 9 | |
| 1868 | ||
| 1870 | LHB Light List (All Coasts): 10 | |
| 1878-1879 | LHB Light List (All Coasts): 12 | |
| 1886 | ||
| 1888 | LHB Light List (All Coasts): 13 | |
| 1893 | F W. W141/4. | LHB Light List (Atlantic): 15 |
| 1898-1899 | Fl W 15s. W141/4. | |
| 1905 | ||
| 1908 | ||
| 1915 | Fl W 15s. W14. fl 2. | USLHS Light List (Atlantic): 15 |
| 1917 | USLHS Light List (Atlantic): 17 | |
| 1920 | ||
| 1927 | ||
| 1931 | ||
| 1935 | Fl W 15s. W14. fl 1.3. | USLHS Light List (Atlantic): 19 |
| 1940 | USCG Light List (Atlantic): 22 | |
| 1943 | USCG Light List (Atlantic): 24 | |
| 1945-1947 | ||
| 1950-1952 | Fl W 15s. W14. fl 1.5. | |
| 1953-1955 | USCG Light List - Vol. I-VI: 1 | |
| 1957 | ||
| 1959-1960 | USCG Light List - Vol. I-V: 1 | |
| 1961 | USCG Light List - Vol. I: 1 | |
| 1963 | ||
| 1964-1966 | Fl(2) W 15s. W14. fl 0.2, ec 3, fl 0.2, ec 11.6. | |
| 1969-1972 | ||
| 1973-1976 | Fl(2) W 15s. W25. fl 0.2, ec 3, fl 0.2, ec 11.6. | |
| 1977-1979 | Fl W 15s. W24. | |
| 1982 | ||
| 1987 | USCG Light List - Vol. I: 5 | |
| 1990-1993 | ||
| 1994-1996 | Fl W 15s. W18. | |
| 2004 | Fl W 15s. W20. |
Historical Light List Optics and Structures
| 1839 | 10 Lamps / 14" Refl. | 8 | 561/2 | Light on keeper's dwelling. | USLHE Light List (US): 20 |
| 1849 | 12 Lamps / 21" Refl. | 42 | |||
| 1858 | 3rd | 60 | 75 | N/A | LHB Light List (US): 12 |
| 1860 | Light on keeper's dwelling. | LHB Light List (US): 9 | |||
| 1865 | LHB Light List (All Coasts): 9 | ||||
| 1866 | N/A | ||||
| 1868 | |||||
| 1870 | Tower of granite, detached from dwelling. Dwelling one story, granite, whitewashed, standing near tower. | LHB Light List (All Coasts): 10 | |||
| 1878-1879 | Tower of granite, natural color, detached from dwellings. Dwelling a one story granite house whitewashed, and a one and a half story wooden house, painted cream color, standing near the tower. | LHB Light List (All Coasts): 12 | |||
| 1886 | Gray-granite tower. Two white dwellings near. | ||||
| 1888 | Gray granite tower. Two white dwellings near. Pyramidal skeleton bell-tower, about 275 S. S.W. of tower. | LHB Light List (All Coasts): 13 | |||
| 1893 | 51 | Gray granite tower. Two white dwellings near. Pyramidal skeleton bell-tower, about 275 SSW. of tower. | LHB Light List (Atlantic): 15 | ||
| 1898-1899 | 4th | Conical, gray granite tower. Two white dwellings near. Pyramidal skeleton bell tower, about 275 feet SSW. of tower. | |||
| 1905 | Conical, gray granite tower. Two white dwellings near. Pyramidal skeleton bell-tower, about 275 feet SSW. of tower. Red-brick oilhouse near base of light-tower, on westerly side. | ||||
| 1908 | Conical, gray granite tower; two white dwellings near; pyramidal skeleton bell-tower about 275 feet SSW'ly of light-tower; red-brick oilhouse near base of light-tower, on W'ly side. | ||||
| 1915 | N/A | 56 | Conical, gray-granite tower. | USLHS Light List (Atlantic): 15 | |
| 1917 | 58 | USLHS Light List (Atlantic): 17 | |||
| 1920 | |||||
| 1927 | |||||
| 1931 | 4 iov | Conical gray-granite tower. | |||
| 1935 | 4 ei | USLHS Light List (Atlantic): 19 | |||
| 1940 | 4 e | USCG Light List (Atlantic): 22 | |||
| 1943 | USCG Light List (Atlantic): 24 | ||||
| 1945-1947 | |||||
| 1950-1952 | |||||
| 1953-1955 | N/A | Conical gray granite tower. | USCG Light List - Vol. I-VI: 1 | ||
| 1957 | |||||
| 1959-1960 | USCG Light List - Vol. I-V: 1 | ||||
| 1961 | USCG Light List - Vol. I: 1 | ||||
| 1963-1966 | |||||
| 1969-1979 | |||||
| 1982 | |||||
| 1987 | USCG Light List - Vol. I: 5 | ||||
| 1990-1996 | |||||
| 2004 |
Historical Light List Audible Fog Signals
| 1858 | Fog-bell rung by machinery | None | LHB Light List (US): 12 |
| 1860 | LHB Light List (US): 9 | ||
| 1865-1866 | LHB Light List (All Coasts): 9 | ||
| 1868 | |||
| 1870 | A bell struck by machinery. | LHB Light List (All Coasts): 10 | |
| 1878-1879 | A bell, struck by hand | LHB Light List (All Coasts): 12 | |
| 1886 | Hand-bell, rung in answer to signals. | ||
| 1888 | Bell struck by machinery, every 10 sec. | LHB Light List (All Coasts): 13 | |
| 1893 | 3d-class Daboll trumpet, blast 7 sec., silent intervals 40 sec. | If trumpet be disabled, a bell will be run by hand. | LHB Light List (Atlantic): 15 |
| 1898 | 3d-class Daboll trumpet, blasts 3 sec., silent intervals 17 sec. | ||
| 1899 | 3d-class Daboll trumpet, blasts 5 sec., alternate silent intervals 20 and 30 sec. | ||
| 1905 | 3d-class Daboll trumpet, blasts 5 sec., one silent interval 25 sec., two silent intervals 10 sec. | If trumpet be disabled a bell will be run by hand. | |
| 1908 | 1st-class Daboll trumpet, blasts 5 sec., one silent interval 25 sec., two silent intervals 10 sec. | ||
| 1915 | 1st-cl. reed horn; gp. 3 blasts every 60 sec., silent 25 sec., blasts each 5 sec. duration | None | USLHS Light List (Atlantic): 15 |
| 1917 | 1st-cl. reed horn; gp. 3 blasts every 60 sec., blasts each 5 sec. duration, silent 25 sec. | USLHS Light List (Atlantic): 17 | |
| 1920 | Bell (hand) if horn is disabled. | ||
| 1927 | 1st-cl. reed horn; gp. 3 blasts every 60 sec., 1st blast 5 sec, silent 10 sec., 2d blast 5 sec., silent 10 sec., 3d blast 5 sec., silent 25 sec.. | Bell (1,200-lb.) if horn is disabled. | |
| 1931 | HORN, 1st-cl. reed; gp. 3 blasts every 60 sec., 3 blasts 5 sec. each, 2 silences 10 sec. each, 1 silence 25 sec. | Bell if horn is disabled. | |
| 1935 | USLHS Light List (Atlantic): 19 | ||
| 1940 | HORN, diaphragm, air; group of 2 blasts every 30 sec,; blast 2 sec., silent 1 sec., blast 1 sec., silent 26 sec. | USCG Light List (Atlantic): 22 | |
| 1943 | USCG Light List (Atlantic): 24 | ||
| 1945-1946 | |||
| 1947 | HORN, diaphragm, air; group of 2 blasts every 30 sec.; blast 2 sec., silent 1 sec., blast 1 sec., silent 26 sec. | ||
| 1950-1952 | |||
| 1953 | HORN, diaphragm; when operating is synchronized with radiobeacon ev 3 minutes for distance finding. | Bell, hand, gp of 2 strokes ev 30s, if horn is disabled. | USCG Light List - Vol. I-VI: 1 |
| 1954-1955 | HORN, diaphragm; when operating is synchronized with radiobeacon ev 3 minutes for distance finding. | ||
| 1957 | |||
| 1959-1960 | USCG Light List - Vol. I-V: 1 | ||
| 1961 | None | USCG Light List - Vol. I: 1 | |
| 1963 | HORN, diaphragm; gp of 2 unequal blasts ev 30s (2sbl-1ssi-1sbl-26ssi). | ||
| 1964-1966 | HORN, diaphragm Mo. (N); gp of 2 blasts ev 30s (2sbl-1ssi-1sbl-26ssi). | ||
| 1969-1970 | HORN, diaphragm; 2 blasts ev 30s (2sbl-1ssi-1sbl-26ssi). | ||
| 1971-1972 | HORN, diaphragm; 2 blasts ev 30s (2sbl-2ssi-2sbl-24ssi). | ||
| 1973-1975 | HORN, 2 blasts ev 30s (2sbl-2ssi-2sbl-24ssi). | ||
| 1976-1979 | HORN: 2 blasts ev 30s (2sbl-2ssi-2sbl-24ssi). | ||
| 1982 | HORN: 2 blasts ev 30s (2s bl-2s si-2s bl-24s si). | ||
| 1987 | HORN: 2 blasts ev 30s (2s bl-2s si-2s bl-24s si). | USCG Light List - Vol. I: 5 | |
| 1990-1996 | HORN: 2 blasts ev 30s (2s bl-2s si-2s bl-24s si). | ||
| 2004 | HORN: 2 blasts ev 30s (2s bl-2s si-2s bl-24s si). |
Historical Light List Other Signals
| 1927 | None | USLHS Light List (Atlantic): 17 |
| 1931 | ||
| 1935 | RADIOBEACON: Transmits gps. of   . |
USLHS Light List (Atlantic): 19 |
| 1940 | RADIOBEACON: Transmits on 288 kc, groups of 1 dash, 3 dots, (). Antenna lead in at light tower. DISTANCE-FINDING STATION. |
USCG Light List (Atlantic): 22 |
| 1943 | USCG Light List (Atlantic): 24 | |
| 1945-1947 | ||
| 1950-1952 | ||
| 1953-1955 | RADIOBEACON: 288 kc. (Code: ). Antenna at light tower. |
USCG Light List - Vol. I-VI: 1 |
| 1957 | ||
| 1959-1960 | USCG Light List - Vol. I-V: 1 | |
| 1961 | USCG Light List - Vol. I: 1 | |
| 1963 | RADIOBEACON: Antenna at light tower. Distance finding station. | |
| 1964-1965 | RADIOBEACON: 314 kc. (Code:). Antenna at light tower. Distance finding station. |
|
| 1966 | RADIOBEACON: Antenna at light tower. Distance finding station. | |
| 1969-1973 | RADIOBEACON: 314 kc. (Code:). Antenna at light tower. Distance finding station. |
|
| 1974 | RADIOBEACON: 314 kc. (Code:). Antenna at light tower. |
|
| 1975-1977 | RBN: 314 kHz () I. Antenna at light tower. |
|
| 1978-1979 | None | |
| 1982 | ||
| 1987 | USCG Light List - Vol. I: 5 | |
| 1990-1996 | ||
| 2004 |
 |
1830 - Present (Exact location of current 1847 lighthouse. Location of original 1830 lighthouse is assumed to be close.) |