650
LIGHTHOUSE
Table VII.—Typical Non-Electric Lighthouse Apparatus.
| Name. | Locality. | Character- istic. |
Period. | Duration of Flashes. | Candle- Power in Standard Candles (Service Intensity). |
Focal Distance of Lens. | Ratio of Angular Breadth of Panel to Whole Circle. |
Illuminant. | Burner. | Service Candle-power of Burner. | Height above High Water. | Year Estab- lished.* |
Remarks. |
| Secs. | Secs. | mm. | Feet. | ||||||||||
| Casquets | Channel Islands | 3 flash | 30 | 1.5 | 185,000 | 920 | 1 : 9 | Incandescent petroleum vapour |
“Matthews” 3-50 mm. dia. mantles | 3300 | 120 | 1877 | Dioptric holophote, 12612° vertical angle; 3 sides of 3 panels in each. |
| Eddystone | South Devon | 2 flash | 30 | 1.5 | 292,000 | 920 | 1 : 12 | do. | do. | 3300 | 133 | 1882 | Biform apparatus, lens elements only, 92° vertical angle; 6 sides of 2 panels each. |
| Bishop Rock | Scilly Isles | 2 flash | 60 | 4.0 | 622,000 | 1330 | 1 : 10 | do. | do. | 3300 | 134 | 1886 | Biform apparatus, lens elements only, 80° vertical angle; 5 sides of 2 panels each. |
| Spurn Point | Yorkshire | Single flash | 20 | 1.5 | 519,000 | 1330 | 1 : 6 | do. | do. | 3300 | 120 | 1895 | Lens elements only, 80° vertical angle. |
| Lundy Island | Bristol Channel | 2 flash | 20 | .33 | 374,000 | 920 | Nearly 1 : 4 | do. | do. | 3300 | 165 | 1897 | Mercury rotation, 4-panel bivalve. [St. Mary’s Isle, Northumberland (1898), is similar.] |
| Pendeen | Cornwall | 4 flash | 15 | .25 | 190,000 | 920 | 1 : 8 | do. | do. | 3300 | 195 | 1900 | 80° vertical angle lens, 2 sides of 4 panels each, mercury rotation. |
| Roker Pier | Sunderland | Single flash | 5 | .10 | 175,000 | 500 | Nearly 1 : 2 | do. | “Chance” 55 mm. dia. mantle | 1200 | 83 | 1903 | Mercury rotation; univalve 164° in azimuth, with 164° dioptric mirror in rear. |
| Bell Rock | Near Firth of Tay | Red and white flashes alter- nately every 30 secs. |
60 | .50 | 392,000 | 920 and 1330 | White about 1 : 9 red about 1 : 2.2 |
do. | “Chance” 55 mm. dia. mantle | 1200 | 93 | 1902 | Combined hyper-radial and first-order light with back prisms in white and mirrors in red. Revolves in 60 secs. [Holy Island, 1905 (Lamlash), similar, flash every 15 secs.] |
| Kinnaird’s Head | Aberdeenshire | Single flash | 15 | .50 | 881,000 | 920 and 1330 | 1 : 2.2 | do. | do. | 2150 | 120 | 1903 | Composite apparatus; panels of 1330 mm. and 920 mm. focal distance; 2 faces. |
| Tarbet Ness | Dornoch Firth | 6 flash | 30 | .50 | 89,000 | 700 | 1 : 12 | do. | “Chance” 55 mm. dia. mantle | 1200 | 175 | 1892 | 6 panels (lens) of 30° with 180° mirror. [Douglas Head (Isle of Man) similar.] |
| Sule Skerry | West of Orkneys | 3 flash | 30 | 1.0 | 378,000 | 1330 | 1 : 9 | do. | “Chance” 85 mm. dia. mantle | 2150 | 113 | 1895 | Equiangular lenses. |
| Pladda | South end of Arran Island | 3 flash | 30 | .50 | 597,000 | 1330 | 1 : 6 | do. | do. | 2150 | 130 | 1901 | 3 equiangular lens panels with mirror in rear; side panels eccentric. [Hyskin Rocks (1904) similar.] |
| Tory Island | Co. Donegal | 3 flash | 60 | 3.0 | 17,000 to 326,000 | 1330 | 1 : 6 | Coal Gas | Wigham, 108 jets (maximum) | 2300 (max.) | 130 | 1887 | Triform apparatus, vertical angle of lenses 65°; 6 sides, one revolution in 6 minutes. The single flash from lens is divided by eclipsing burner into 3 flashes. |
| Fastnet | Co. Cork | Single flash | 5 | .17 | 750,000 | 920 | 1 : 4 | Incandescent petroleum vapour |
Irish pattern 50 mm. mantle | 1200 | 160 | 1904 | Biform apparatus; 4 panels of 90° vertical angle and 90° in azimuth; mercury rotation. |
| Kinsale | do. | 2 flash | 10 | .25 | 460,000 | 920 | 1 : 6 | do. | do. | 1200 | 236 | 1907 | Biform apparatus, 3 sides each of 2 panels; vertical angle 96°; mercury rotation. [St. John’s Point, Co. Down (1908) similar, period 7.5 secs.] |
| Howth Bailey | Dublin Bay | Single flash | 30 | 1.0 | 950,000 | 920 | 13 : 32 | do. | Irish pattern 3-50 mm. dia. mantles | 3300 | 134 | 1902 | Bivalve apparatus; panels of 147° in azimuth and 122° vertical angle; mercury rotation. |
| Chassiron | Bay of Biscay | Single flash | 10 | 1.0 | 70,000 | 920 | 1 : 8 | Oil | 6 wick | 480 | 164 | 1891 | The old first-order apparatus has been utilized in all cases. |
| .50 | 180,000 | 920 | 1 : 8 | Incandescent oil gas |
30 mm. dia. mantle | 400 | 164 | 1895 | |||||
| .70 | 360,000 | 920 | 1 : 8 | Incandescent acetylene |
55 mm. dia. mantle | 1300 | 164 | 1902 | |||||
| Cap d’Antifer | English Channel | Single flash | 20 | 1.0 | 400,000 | 1330 | 1 : 6 | Incandescent petroleum vapour |
French pattern 85 mm. mantle | 2150 | 394 | 1894 | Mercury rotation, hyper-radial apparatus with reflecting prisms. This is the only apparatus of this focal distance on the French coast. |
| Île de Batz | Finistère | 4 flash | 25 | .37 | 200,000 | 920 | 1 : 8 | do. | do. | 2150 | 223 | 1900 | Group-flashing apparatus; 4 panels of 45°, with 180° mirror in rear; mercury rotation. |
| Ar’men | do. | 3 flash | 20 | .38 | 200,000 | 700 | 1 : 5 | do. | do. | 2150 | 94 | 1897 | Mercury rotation; 3 panels, mirror in rear. |
| Villefranche | Mediterranean | Single flash | 5 | .38 | 250,000 | 700 | 1 : 4 | do. | do. | 2150 | 229 | 1902 | Mercury rotation. |
| Île Vierge | Finistère | Single flash | 5 | .38 | 500,000 | 700 | 1 : 4 | do. | do. | 2150 | 252 | 1902 | Twin optic; mercury rotation. |
| Kennery Island | Bombay | 2 flash | 10 | .25 | 250,000 | 920 | Nearly 1:4 | do. | 70 mm. dia. mantle | 1400 | 153 | 1902 | Mercury rotation; bivalve apparatus; 2 double-flashing 170° panels. |
| Cape Race | Newfoundland | Single flash | 7.5 | .30 | 1,100,000 | 1330 | 1 : 4 | do. | “Chance” 85 mm. dia. mantle | 2150 | 165 | 1907 | 4 panels, vertical angle 12112°; mercury rotation. [Manora Point, Karachi, 1909, similar.] |
| Pachena Point | British Columbia | 2 flash | 7.5 | .44 | 220,000 | 920 | 1 : 8 | do. | do. | 2150 | .. | 1908 | Mercury rotation. 4 sides of 2 panels each. |
| Cape Hermes | Cape Colony | Single flash | 3 | .31 | 30,000 | 250 | 1 : 3 | do. | “Chance” 55 mm. dia. mantle | 1200 | 175 | 1904 | 3 panels, vertical angle 150°; mercury rotation. |
| Hood Point | do. | 4 flash | 40 | .58 | 200,000 | 920 | 1 : 8 | do. | “Chance” 85 mm. dia. mantle | 2150 | 180 | 1895 | Mercury rotation; 4 panels of 45° in azimuth and 80° vertical angle, with catadioptric mirror in rear. |
| Cape Naturaliste | West Australia | 2 flash | 10 | .15 | 450,000 | 920 | About 1 : 3 | do. | do. | 2150 | 404 | 1904 | Mercury rotation; 2 lenses of 12612° in azimuth, with mirror of 107°. |
| Point Cloates | do. | Single flash | 5 | .30 | 300,000 | 700 | 1 : 3 | do. | do. | 2150 | 190 | 1909 | Mercury rotation; 3 panels, each 120° in azimuth and 13312° vertical angle. |
| Pecks Ledge | Connecticut, U.S.A. | 2 flash | 30 | .50 | 10,000 | 250 | 1 : 4 | do. | 34 mm. dia. mantle | 300 | 54 | 1906 | Rotated on ball bearings. 2 lenses of 90° each and mirror. |
| Fire Island | New York, U.S.A. | Single flash | 60 | 4.0 | 250,000 | 920 | 1 : 8 | do. | 55 mm. dia. mantle | 1000 | 167 | 1858 | Rotated on roller bearings. |
| Gray’s Harbor | Washington, Pacific Coast, U.S.A. | Alternating red and white flashes |
5 | .20 | White 10,000 red 8,000 | 500 | .. | Oil | 3 wick | 160 | 122 | 1898 | Mercury rotation; one (red) lens of 170° in azimuth, reinforced by two 60° mirrors; one (white) lens of 60° in azimuth. |
* The dates given are of the establishment of the optical apparatus. In many cases incandescent burners have been installed at later dates.
