Halfway Rock (Maine)
Historical Light List Characteristics
| 1878-1879 | AlF W Fl R 60s. W15, R15. | LHB Light List (All Coasts): 45 |
| 1886 | LHB Light List (All Coasts): 44 | |
| 1888 | LHB Light List (All Coasts): 46 | |
| 1893 | AlF W Fl R 90s. W15, R15. | LHB Light List (Atlantic): 53 |
| 1898 | AlF W Fl R 90s. W141/4, R141/4. | LHB Light List (Atlantic): 60 |
| 1899 | LHB Light List (Atlantic): 61 | |
| 1905 | LHB Light List (Atlantic): 64 | |
| 1908 | LHB Light List (Atlantic): 66 | |
| 1915 | AlF W Fl R 90s. W14, R14. fl 5. | USLHS Light List (Atlantic): 74 |
| 1917 | USLHS Light List (Atlantic): 78 | |
| 1920 | ||
| 1927 | USLHS Light List (Atlantic): 80 | |
| 1931 | F W, Alt F and Fl R, 90s. W14 R14. fl 5. | |
| 1935 | ||
| 1940 | F W, Alt F and Fl R, 90s. W14 R14. fl 1.7. | USCG Light List (Atlantic): 90 |
| 1943 | USCG Light List (Atlantic): 111 | |
| 1945-1947 | ||
| 1950-1952 | ||
| 1953-1955 | USCG Light List - Vol. I-VI: 6 | |
| 1957 | ||
| 1959-1960 | USCG Light List - Vol. I-V: 6 | |
| 1961 | USCG Light List - Vol. I: 6 | |
| 1963-1964 | ||
| 1965-1966 | F W, Alt F and Fl R, 90s. W14 R14. F W 59s, F R 14s, Fl R(bright) 3s, F R 14s. | |
| 1969-1972 | ||
| 1973-1975 | F W, Alt F and Fl R, 90s. W21 R16 R(bright)25. F W 59s, F R 14s, Fl R(bright) 3s, F R 14s. | |
| 1976 | Fl R 6s. R19. | |
| 1977-1979 | Fl R 5s. R19. | |
| 1982 | ||
| 1987 | USCG Light List - Vol. I: 35 | |
| 1990-1992 | ||
| 1993-1996 | USCG Light List - Vol. I: 40 | |
| 2004 |
Historical Light List Optics and Structures
| 1878-1879 | 3rd | 66 | 80 | Tower of granite, natural color. | LHB Light List (All Coasts): 45 |
| 1886 | Gray- granite tower, appearing to stand in the water. | LHB Light List (All Coasts): 44 | |||
| 1888 | Gray granite tower, appearing to stand in the water. Pyramidal skeleton bell-tower to S.W. of tower. | LHB Light List (All Coasts): 46 | |||
| 1893 | 653/4 | 753/4 | Gray granite tower, with frame boathouse attached on NW. side. Pyramidal skeleton bell tower to SW. of tower, and elevated pyramidal oil house northwesterly of it. | LHB Light List (Atlantic): 53 | |
| 1898 | LHB Light List (Atlantic): 60 | ||||
| 1899 | LHB Light List (Atlantic): 61 | ||||
| 1905 | White, granite tower, with white dwelling attached to northwesterly side. Pyramidal skeleton bell tower to SW. of tower, and elevated pyramidal oil house northwesterly of it. | LHB Light List (Atlantic): 64 | |||
| 1908 | White, granite tower, with white dwelling attached to NW'ly side; pyramidal skeleton bell-tower SW'ly and elevated pyramidal oil-house NE'ly of light tower. | LHB Light List (Atlantic): 66 | |||
| 1915 | N/A | 72 | 76 | White; granite tower attached to dwelling. | USLHS Light List (Atlantic): 74 |
| 1917 | 77 | USLHS Light List (Atlantic): 78 | |||
| 1920 | |||||
| 1927 | USLHS Light List (Atlantic): 80 | ||||
| 1931 | 3 iov | White granite tower attached to dwelling. | |||
| 1935 | |||||
| 1940 | 3 e | USCG Light List (Atlantic): 90 | |||
| 1943 | USCG Light List (Atlantic): 111 | ||||
| 1945-1947 | |||||
| 1950-1952 | |||||
| 1953-1955 | N/A | USCG Light List - Vol. I-VI: 6 | |||
| 1957 | |||||
| 1959-1960 | USCG Light List - Vol. I-V: 6 | ||||
| 1961 | USCG Light List - Vol. I: 6 | ||||
| 1963-1966 | |||||
| 1969 | N/A | ||||
| 1970-1979 | 77 | ||||
| 1982 | 76 | 77 | |||
| 1987 | USCG Light List - Vol. I: 35 | ||||
| 1990-1992 | White tower attached to dwelling. | ||||
| 1993-1996 | USCG Light List - Vol. I: 40 | ||||
| 2004 |
Historical Light List Audible Fog Signals
| 1878-1879 | None | None | LHB Light List (All Coasts): 45 |
| 1886 | Hand-bell, rung in answer to signals. | LHB Light List (All Coasts): 44 | |
| 1888 | Bell struck by machinery every 10 sec. | LHB Light List (All Coasts): 46 | |
| 1893 | LHB Light List (Atlantic): 53 | ||
| 1898 | LHB Light List (Atlantic): 60 | ||
| 1899 | LHB Light List (Atlantic): 61 | ||
| 1905 | LHB Light List (Atlantic): 64 | ||
| 1908 | 1st class Daboll trumpet; blasts alternately 8 and 4 sec., silent intervals alternately 4 and 44 sec. | If trumpet be disabled a bell will be struck by machinery a single blow every 10 sec. | LHB Light List (Atlantic): 66 |
| 1915 | 1st-cl. reed horn; gp. 2 unequal blasts every 60 sec.: 1st blast 8 sec., silent 4 sec., 2d blast 4 sec., silent 44 sec. | Bell, if horn is disabled, 1 stroke every 10 sec. | USLHS Light List (Atlantic): 74 |
| 1917 | USLHS Light List (Atlantic): 78 | ||
| 1920 | |||
| 1927 | Bell (1,200-lb.), if horn is disabled, 1 stroke every 10 sec. | USLHS Light List (Atlantic): 80 | |
| 1931 | HORN, 1st-cl. reed; gp. 2 blasts every 60 sec. Blast 4 sec., silent 2 sec., blast 4 sec., silent 50 sec. | Bell, if horn is disabled, 1 stroke every 15 sec. | |
| 1935 | |||
| 1940 | HORN, diaphragm, air; group of 2 blasts every 60 sec. Blast 3 sec., silent 3 sec., blast 3 sec., silent 51 sec. | USCG Light List (Atlantic): 90 | |
| 1943 | USCG Light List (Atlantic): 111 | ||
| 1945-1947 | HORN, diaphragm, air; group of 2 blasts every 60 sec. Blast 3 sec., silent 3 sec., blast 3 sec., silent 51 sec. | ||
| 1950-1952 | |||
| 1953 | HORN, diaphragm; when operating, is synchronized with radiobeacon ev 3 minutes for distance finding. | Bell, 1 stroke ev 15s, if horn is disable | USCG Light List - Vol. I-VI: 6 |
| 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: 6 | ||
| 1961 | USCG Light List - Vol. I: 6 | ||
| 1963-1966 | HORN, diaphragm; gp of 2 blasts ev 60s (3sbl-3ssi-3sbl-51ssi). | None | |
| 1969-1972 | HORN, diaphragm; 2 blasts ev 60s (3sbl-3ssi-3sbl-51ssi). | ||
| 1973-1975 | HORN, 2 blasts ev 60s (3sbl-3ssi-3sbl-51ssi). | ||
| 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: 35 | |
| 1990-1992 | |||
| 1993-1996 | USCG Light List - Vol. I: 40 | ||
| 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): 80 |
| 1931 | ||
| 1935 | ||
| 1940 | USCG Light List (Atlantic): 90 | |
| 1943 | USCG Light List (Atlantic): 111 | |
| 1945 | RADIOBEACON: Transmits on 312 kc., groups of 3 dashes ( ). Antenna lead-in 30 feet 160° from light tower. DISTANCE-FINDING STATION. |
|
| 1946-1947 | RADIOBEACON: Transmits on 312 kc., groups of 3 dashes, (). Antenna lead-in 30 feet 160° from light tower. DISTANCE-FINDING STATION. |
|
| 1950-1952 | ||
| 1953-1955 | RADIOBEACON: 312 kc (Code: ). Antenna 30 feet 160° from light tower. |
USCG Light List - Vol. I-VI: 6 |
| 1957 | ||
| 1959-1960 | USCG Light List - Vol. I-V: 6 | |
| 1961 | USCG Light List - Vol. I: 6 | |
| 1963 | RADIOBEACON: Antenna 30 feet 160° from light tower. Distance finding station. | |
| 1964-1965 | RADIOBEACON: 314 kc (Code:). Antenna 30 feet 160° from light tower. Distance finding station. |
|
| 1966 | RADIOBEACON: Antenna 30 feet 160° from light tower. Distance finding station. | |
| 1969-1973 | RADIOBEACON: 314 kc (Code:). Antenna 30 feet 160° from light tower. Distance finding station. |
|
| 1974 | RADIOBEACON: 314 kc (Code:). Antenna 30 feet 160° from light tower. |
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| 1975 | RBN: 314 kHz () IV. Antenna 30 feet 160° from light tower. |
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| 1976 | RBN: 314 kHz () IV. Antenna on light tower. |
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| 1977 | RBN: 314 kHz (  ) IV. Antenna on light tower. |
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| 1978 | RBN: 291 kHz (). Antenna on light tower. |
|
| 1979 | RBN: 291 kHz HR (). Antenna on light tower. |
|
| 1982 | ||
| 1987 | USCG Light List - Vol. I: 35 | |
| 1990 | RBN: 291 kHz HR (). Antenna on light tower. |
|
| 1991 | 291 kHz. HR (). Antenna on light tower. |
|
| 1992 | FREQ: 291 kHz. HR (). Antenna on light tower. |
|
| 1993-1996 | None | USCG Light List - Vol. I: 40 |
| 2004 |
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1871 - Present |