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LIGHTHOUSES OF THE CAPE COLONY As an introduction to the description of the lighthouses of Cape Colony which forms the subject of this paper, it is desirable to refer briefly to the system of administration now obtaining. The Coast lighthouses are under the sole control of the Public Works Department. This Department is directly responsible for the employment and training of the light keeping staff, the maintenance of the existing lights and fog signals, the provision of new lights and the construction of all towers and other buildings therefore. In addition, this Department maintains all beacons, buoys and signal stations in the Colony with the exception of some few small harbour lights maintained by the local harbour authorities at Cape Town, Simonstown, Port Elizabeth and East London. Contrary to the practice which obtains in the United Kingdom and some other countries, no light dues are levied on shipping by, or in the Colony, the entire cost of coast lighting being provided out of the Colonial Revenue. Thus the funds for the maintenance and improvement of existing lights and the provision of new lights are dependent on the will of Parliament. The Author does not propose to discuss either the merits or demerits of this system. The progress in the methods of coast lighting has been extensive of late years. Smeaton's early effort at the famous Eddystone was but a step in advance of the beacon fires, and was a mere chandelier holding 24 tallow candles of two-fifths of a pound each, and having a power of 2.8 standard candles. The entire power of the 24 candles amounted to 67.2 candles, and at present rates would be at a cost of nearly 4s. per hour. When one compares this with a modern light of half a million candles power at a cost of 21/2d. per hour, the difference is striking. Lighting apparatus may be divided into three classes: first Catoptric, in which the light is merely reflected. Second, Cata-dioptric, in which reflectors are used in conjunction The latter is the most modern and efficient method of lighting. The illuminants have also undergone extensive changes, and may be classed in orde4r of merit as follows: Candles, wickburners consuming fish or colza oils, wickburners consuming petroleum, electric light, incandescent petroleum - vapour burners. The system of ignited petroleum vapour for the incandescence in the Welsbach mantle has been in use in France since 1898, in England since 1902, and in this Colony since 1903. The advantage of this incandescent burner above all others may be understood from the fact that by its introduction in this Colony most of our lights have been increased in power by over 400 percent and with a reduction in oil consumption of 40 percent. The vapour burners used in this Colony are of three sizes, ie
A glance at the map will show that the first light on the coast of the Colony going West to East is Dassen Island. NOTE.- In calculating the geographical range of a light, it is usual to take the range due to elevation of the focal plane above the level of high water, and to add to this the additional range obtained by virtue of the eye of the observer above sea level, which is assumed to be 15 feet. The addition to the actual range of the light is therefore 4.44 nautical miles or roughly 4 1/2 nautical miles. This addition is made in stating the range of lights in all official lists of lights and is included in the ranges given in this paper. In the case of some lights of small power the effective range is less than the theoretical geographical range owing to loss of power in the beam to penetrate the atmosphere so far as the horizon. The tower which is circular in plan and 95 feet in height from the ground level to lantern balcony is constructed of cast iron segments, the flanges of which are bolted together internally. The tower is founded upon and secured to a massive base of granite masonry 15 feet in height which also serves to provide accommodation for stores. The lantern is 12 feet internal diameter with circular glazing and vertical and horizontal framing. It is surmounted by a double sheeted copper dome with a Trinity House pattern ventilator. The optical apparatus is of the first order, diptric of 920 m/m focal radius emitting a double flashing white light of the following period:-
The optic is four-sided, each side being sub-divided so as to produce two flashes. One revolution of the apparatus therefore produces 8 flashes or 4 complete periods, and is made in 120 seconds. The moving portion of the optic weighing about 3 tons is supported on a set of 8 vertical steel rollers and guided horizontally by 16 brass rollers. The necessary motive power is derived from a weight driven clock regulated by a "Slight" governor. The actual driving weight is 6 cwts. and the clock regulated wound. A speed indicator is fitted as well as hand turning gear for use in case of derangement of the driving machine. The illuminant in use when the light was first erected was a 6 wick Trinity House Douglass burner, giving a power to the beam of 47,000 candles, and having a yearly consumption of 1,800 gallons of mineral oil of specially heavy grade. During 1906 these burners were replaced by incandescent oil vapour burners having a mantle of 85 m/m diameter. The use of this burner has increased the power of the beam to 180,000 candles, at the same time bringing about a smaller consumption of oil and a resultant saving in cost of maintenance of 80 per annum. Communication is maintained with the Island by steamer once a month and by pigeon post. Proposals have been framed to provide communication by means of aetheric signalling, but these have not yet been carried into effect. Proceeding, the next light on the list is Robben Island in Table Bay. This light, which was built in 1865, is situated in latitude 33 degrees 48.9' S, longitude 18 degrees 22.5' E, and has a range of 18 miles; the focal plane being 154 feet above high water. The tower, circular in plan, is built of masonry and is 60 feet high from ground level to balcony. The lantern is circular with a cast iron base or murette. The glazing is flat, set in inclined frames. The dome is of copper, double lined, and ventilated by means of a revolving perforated ball cowl. Until 1907, the illuminating apparatus consisted of a first order dioptric fixed lens belt with upper and lower refracting zones and exhibiting a fixed white light of a little over 5,000 candle power. By the simple expedient of providing a set of revolving
screens carried on an aluminium float in a mercury bath the
apparatus was in 1907 converted into an occulting light with While this alteration in the characteristic of, light was in progress, advantage was taken of the opportunity to increase the power of the beam and an 85 m/m vapour burner installation was provided which increased the power of the light to 23,000 candles. The wreck of the TANTALLON CASTLE on Robben Island in 1901 impressed upon the Government the urgent necessity for the provision of a fog signal at this point, and in 1902 an explosive signal was erected in connection with the lighthouse. It may be of interest to mention that the average fog duration at Robben Island is practically the same as the average for the English Channel, viz, 430 hours. The fog signal apparatus consists of a steel mast surrounded at its base by a sheet steel cabin containing the necessary stores and electric battery. The charge, which is fired once in 5 minutes, consists of 4 ounces of "Tonite" or nitrated gun cotton, into which is inserted a fulminate of mercury detonator. The cartridge is attached to the end of two conductors which are secured to an electrical contact plate. This contact maker is hoisted by means of a flexible steel
cable passing over a pulley at the mast head and attached to
a small hand winch near the base of the mast. The contact
plate at the end of the travel of the cable completes the
electric circuit by touching similar plates at the jib head
and the charge is thus automatically fired. The practical
range of this signal under average atmospheric conditions is
about 7 miles, although under favourable circumstances it may
be heard over 20 miles. An underground magazine is provided
for the storage of the main supply of explosives and MOUILLE POINT LIGHT in Table Bay was established in 1842, and disestablished on 15th April 1908. It was merely a small leading light to the anchorage. Its place has now been taken by the provision of a small fourth order occulting red light at a seaward end of the harbour breakwater and has rendered the continuance of the Mouille Point Light unnecessary. The new light is lit by electric current. GREEN POINT LIGHT, TABLE BAY The early history of this light is unauthentic, and the Author has been unable to determine its origin from authoritative documents. It is said, however, that the tower was originally a military watch tower maintained by the Dutch upon which beacon fires were lighted. The existing light was erected by the Dutch upon which beacon fires were lighted. The existing light was erected in 1865, and is placed at a height of 65 feet above high water in latitude 33 degrees 54.1' S, longitude 18 degrees 24.1' E and has a range of 13 3/4 miles. The tower is square in plan and built of masonry. It is 52 feet from ground level to the balcony. The upper 20 feet were added when the present light was erected. The lantern is circular in plan with a cast iron murette, flat glazing and vertical and horizontal framing. The double lined copper dome has a perforated ball-shaped ventilator. The optical apparatus is dioptric of the third order of 500 m/m focal radius and consists of 8 revolving panels with upper and lower refracting zones. Each panel produces a white flash once in 10 seconds, thus one complete revolution comprising 8 flashes is performed in 80 seconds. The apparatus when erected was provided with a 2 wick Trinity House pattern burner and had a power of 8,500 candles, the revolving lenses being carried on vertical steel rollers. Owing to the worn condition of the machine and revolving carriage it became necessary to provide new gear in 1906. The opportunity was then taken to do away with the old and
cumbersome rollers and a modern mercury floating apparatus
was installed. With this apparatus the whole of the Green Point Lighthouse is the headquarters of the Lighthouse Relieving Staff, is a training station, and has a workshop at which all mechanical repairs and adjustments of apparatus and burners are made for the whole of the lighthouses by the light keeping staff. CAPE POINT This lighthouse is situated on one of the most beautiful portions of the coast. It is erected on the point at an elevation of nearly 800 feet above the sea. The focal plane of the light is actually 816 feet above high water, and the beam is visible in very clear weather at a distance of 36 miles. The light has a visual arc of 331 degrees 52.5' of which 5 degrees 37.5' is obscured by Vasco de Gama's Peak. Being at such an unusual height, the light is very frequently obscured by passing clouds and mist, the average yearly obscuration being 900 hours, which is only equalled at sea level on the foggy shores of Newfoundland. The tower which is circular in plan is naturally of small height, only 30 feet from the ground level of balcony, and is constructed of cast iron segments bolted together. The light is of antique pattern, a first order catoptric apparatus showing a flash of 12 seconds duration every minute. The burners are of the one wick "Deville" constant level type, and, in conjunction with the parabolic reflectors, emit which includes the provision of a modern and powerful first order light at a low level Diaz Point about 3/4 of a mile from the existing light on Cape Point. The poposed light will have a power of over 400,000 candles, and would be a level out of the range of frequent cloud obscuration, which so impairs the efficiency of the existing light. Owing, however, to the nature of the coast this light cannot be provided until the proposed new light for Slangkop has been erected. Cape Point is a Lloyd's signalling station and is connected with Simonstown by telephone. Provisions are conveyed once in every three months by ox-waggon, and a weekly post carried on donkeys is provided. At this stage mention should be made of the Lighthouses Commission which sat in 1906. The following schemes, prepared by the Author were then recommended:- The provision of a first order light and compressed air syren at Slangkop at an estimated cost of about œÀ16,000. The building of a first order light on a lower site at Cape
Point costing œÀ7,500. At Port Nolloth the erection of a fourth order light and an explosive fog signal. This for signal has since been erected. At Cape ST Blaize, Mossel Bay, the installation of an explosive fog signal. And at Dassen Island and provision of a compressed air fog syren. Unfortunately the financial condition of the Colony has interfered with carrying out of most of these much needed improvements to the coast lighting. Proceeding, the next light is ROMAN ROCK in Simon's Bay. This light was established in 1845, and is the only rock
lighthouse on the coast of Cape Colony. It is erected on the
summit of a rock pinnacle rising out of the sea at the The tower is circular in plan and is formed of cast iron segments bolted together, the lowest ring being secured to the rock. Some time after the construction of the tower was completed, unmistakable signs of collapse appeared which were due to the constantly recurring shocks from sea strokes in stormy weather. In order to give additional weight to the structure and increase its stability and resistance to the sea strokes, a granite base was constructed completely surrounding the lower part of the tower to a height of 20 feet. This addition has had the desired effect of making the structure capable of withstanding the heaviest seas. The height of the tower from rock level to balcony is 45 feet, the focal plane of the light being 54 feet above high water and the range 12 miles. The light is of the catoptric type and similar to that of Cape Point, with the exception that only one reflector is visible at a time, thereby reducing the candle power of beams to a fourth of that of Cape Point where four reflectors arranged in every face. The flash occurs once in 30 seconds, tyhe system of 8 reflectors making a complete revolution in 4 minutes. Communication by day with Simonstown is effected by flag signalling, whilst at night coloured lights are used in cases of emergency. It, however, frequently happens that owing to stormy weather the men have to remain in the tower for several days before they can be relieved, and during these storms the waves break with such force as to drive the crests and broken water over the lanter. On such occasions it is of course impossible for the men to emerge from tower. POINT DANGER LIGHT This light, established in 1895, overlooks the spot where the world-famous wreck of the BIRKENHEAD occurred, and is situated in latitude 34 degrees 37.8' S, longitude 19 degrees The tower, which is 60 feet in height to the lantern floor level, is octagonal in plan and is constructed of concrete. the range of the light is 18 miles, the focal plane being 150 feet above high water. The lantern, circular in plan, is 12 feet in internal diamteter with cast iron murette, circular glazing and rectangualr framing, with a double lined dome and Trinity House pattern ventilator. The apparatus consist of a first order dioptric triple flashing optic of 920 m/m focal radius, showing a white light, the characteristic of which is as follows:-
The optic contains 4 panels of 27 degrees and 8 panels of 31
1/2 degrees and wighs about 3 1/2 tons. It revolves on 8
vertical steel rollers and is guided horizontally by 16 Hand turning gear is also provided for emergency use. The illuminant is a 6 wick Trinity House Douglass burner, fed from two 50 gallon Trinity House pump reservoirs. The intensity of the beam thrown from the optic is 45,000 candles, and the annual consumption of heavy mineral oil is 1,800 gallons. Incandescent oil vapour burners of the most modern type are now about to be installed in place of the existing wick burners. This substitution will increase the candle power of the light by over 400 percent and result in about 40 percent economy of oil. CAPE L'AGULHAS LIGHTHOUSE Cape L'Agulhas, the most Southerly point of Africa, is on the theoretical dividing lines of two oceans. It is one of the most important landfalls to mariners, and yet until recently it has been perhaps the least efficiently lighted headland on our coast. The fact of its great importance to navigation is shewn by the date of the first establishment of a light on the Cape in 1848. The optical apparatus originally installed has existed unaltered in its form until the present year, and its great life makes it of considerable interest. It was one of the very early diptric fixed lenses constructed in France, and a very similar example the Author has seen installed in the Museum of the Depot des Phares at Paris. The apparatus was of the first order and cata-diptric consisting of a fixed cylindrical glass refractor of 920 m/m focal distance with a slivered metallic reflector and two sets of upper and lower reflecting silvered mirrors fitted one above the other below the refracting belt. Until 1905 the illumination employed was that given by a four wick Trinity House burner, the resultant power to the beam from the optic being a trifle over 4,000 candles. In every early years oil manufactured from the tails of Cape
sheep, costing about 10s per gallon was used at this
lighthouse, but by the adoption of the modern incandescent The tower is circular in plan, 63 feet in height and is built of limestone, surmounted by a polygonal lantern with flat glazing and rectangular framing. The focal place of the light is 128 feet above high water. A scheme was prepared by the Author in 1906 to construct a new tower of reinforced concrete on an adjoining site; the height of the poposed tower would have been sufficient to give an elevation of 180 feet to the focal plane of the light. The estimated cost of this scheme was œÀ10,600 and included the provision of a new lighting apparatus and lanter. Financial reasons have prevented the carrying out of this scheme in its entirety, but a modification including the provision of a modern first order flashing light utilizing the existing tower and lantern, involving the expenditure of 4,000 was sanctioned by the Government in 1908. This scheme has recently been completed. The new apparatus consists of 4 panels, each panel subtending a vertical angle of 126 degrees and a horizontal angle of 90 degrees. The lens consists of 4 bulls'-eyes with 8 annular rings, the remainder of the optical elements being cata-diotric prisms. The frames are of gun-metal and carry the entire weight of the lenses, some 6 tons. The optic rotates on a mercury float and makes a revolution in 12 seconds, the weight of the revolving portions being about 8 tons. The mercury bath and float are of cast iron, and are arranged for lowering for inspection and cleaning purposes. The bath is carried on an annular table with screwed sleeve surrounding the shaft of the pedestal. An aperture is left in the table to give access to the interior of the optic. The apparatus and float are maintained in a perfectly central
position by means of guide rollers. Subsidiary steel rollers
with ball bearings are provided for taking the weight of
apparatus when the mercury has been run out. The apparatus
is rotated by means of a weigh-driven clock which is hand
wound, the weight about 400 lbs, being suspended on a
flexible steel cable. The clock is fitted with a "Slight"
governor, and has an electrical speed warning apparatus
ringing a bell in the lantern. In addition the electric bell
attached to the clock is interconected with the top and
bottom of the weight tube indicating when the weight required
re-winding and when it is high enough. Owing to the heavy nature of some of the castings, one of which weighed 27 cwts. the work of erection was somewhat difficult, added to this was the necessity of installing the apparatus without interfering with the existing lantern with a resulting loss of space in which to manoeuvre the castings. The method of hoisting the portions was as follows:- A spar of pitch pine about 30 feet long and 12 inches in diameter tapered at the end was erected on top of the tower and stayed with flexible steel wires to anchors let into the ground. A wire rope gear consisting of single and double iron blocks was led from the winch through a snatch block to the derrick head. The castings were then hoisted high enough to clear the tower balcony (some 63 feet) the derrick topped and the castings finally landed on the balcony. The castings were then dragged along the balcony and passed through an aperture made in the granite base of the lanter. Once inside the castings were each lifted into position by means of a derrick and two Westinghouse purchases. For the passage of the steel driving cable a hole 4 feet 6 inches in depth was drilled through the granite floor of the lantern. The weight tube measuring 60 feet in height and 18 inches in diameter and weighing 24 cwts., was put together inside the tower, the bottom portion being sunk into a hole cut out of the foundations of the tower and passed through each floor and finally jacked up into position and the hole concreted. With the exception of unskilled labour the Author erected this apparatus with the help of the lightkeeper, his assistant and two relieving lightkeepers. During the progress of the work a temporary light made in the workshop at Green POint LIghthouse, was exhibited. The new light exhibits a flash once in 3 seconds and has a range of 81 miles. CAPE ST BLAIZE This light was established in 1864 when a third order fixed red light was erected on the headland which separates Mossel Bay from Fish Bay in latitude 34 degrees 11.2'S, longitude 22 degrees 9.5' E. The focal plane is 240 feet above high water, and the light has a range of 15 miles. The tower which is of masonry, is square in plan. The existing apparatus was erected in 1897, the old tower being utilized for its reception and a new lantern 8 feet internal diameter was provided at the same time. The optical apparatus is a 4th order dioptric double flashing white light of 250 m/m focal distance exhibiting two flashes in rapid succession every 15 seconds. The optic is a bivalve, each lens being subdivided into two panels. The driving clock is actuated by a weight of 150 lbs. and regulated by a horizontal disc governor. The burner is of the 1 wick Trinity House Douglass type and is fed from a constant level oil rervoir. The power of the beam is 4,500 candles. Cape St Blaize is a signalling station, and is the telephonic communication with the office of the Harbour Master of Mossel Bay. CAPE ST FRANCIS This station was built in 1878 and is in latitude 34 degrees 12.5' longitude 24 degrees 50.3' E. and about 45 miles. West of Port Elizabeth. The focal plane of the light is 118 feet above high water. The beam is visible for 16 3/4 miles, and has a white arc of 225 deg. and a red arc of 53 degrees 26'. The tower is 91 feet in height from ground level to balcony is circular in plan and is built of masonry with a 15 foot granite base and balcony. As showing the unusual thickness of the walls of the tower it may be mentioned that a circular staircase is constructed in the thickness of the wall for a height of 40 feet. The lanter pedestal is of cast iron surmounted by flat glazing and inclined framing capped by a double copper cupola with a perforated ball shaped ventilator. The diptric flashing apparatus is of the second order, consisting of 8 lenses with upper and lower refracting prisms, shewing a single white flashing light. Until 1906 the revolving optic was carried upon a set of vertical steel rollers, but the driving machine and revolving carriage being in an unreliable condition owing to excessive wear, it became necessary to renew the mechanism and advantage was taken of the opportunity to substitute the modern system of mercury rotation for the old roller carriage. At the same time the speed of revolution was accelerated from one flash in 20 seconds to one in five seconds, the total revolution being completed in 40 seconds. The entire revolving portions of the apparatus weighing some 4 1/2 tons are now carried on a cast iron annular float revolving in a bath. The driving machine is actuated by a weight of only 60 lbs., suspended on a flexible steel cable and regulated by a "Sight" governor. Simultaneously with the provision of these improvements the power of the light was increased from 15,000 candles to 120,000 candles by the substitution of 85 m/m diameter incandescent oil vapour burner, for the 3 wick burner formerly in use. Communication with Humansdorp by day and Port Elizabeth by night is maintained by telephone. The lighthouse is a Lloyds' signalling station and is manned by a lightkeeper and two assistants. The total cost of the original building and improvements to date has been œÀ27,000. CAPE RECEIFFE This station, established in 1851, is placed on the Cape which forms the western horn of Algoa Bay, overlooking the Thunderbolt Reef, in latitude 34 degrees 1.7' S, longitude 25 degrees 42.2' E. The tower is built on a rock foundation in the midst of a large expanse of sand beach. At high water spring tides during heavy weather with wind from the N.W, the sea comes right round the lighthouse and isolates it from the mainland. The focal plane of the light is 93 feet above high water and it has a range of 15 miles. The light shows red through an arc of 28 degrees 8' over the Roman Rock and white through the remainder of the seward arc of 244 degrees 41'. The tower is constructed of masonry, is octagonal in plan, and has a height of 80 ft. from ground level to balcony. The pedestal of the lantern is also of masonry and is surmounted by polygonal flat glazing in rectangular framing. The copper dome is double lined and has a Trinity House pattern ventilator. The optic is of the first order and consists of a fixed and flashing diptric apparatus. The flashing portion is made up of 8 panels of lenses of 920 m/m focal radius, revolving on a set of 8 vertical steel rollers and guided by 2 sets of 6 each of brass horizontal rollers. A white flash is emitted once in every 60 seconds and a revolution of the apparatus once in 8 minutes. The fixed light is produced by upper and lower belts and refractory prisms. The driving machine, which is of French manufacture, is actuated by a suspended weight and regulated by a fan governor. In 1905 the power of light was increased from 20,000 to 125,000 candles by the substitution of an 85 m/m incandescent oil vapour for the 4 wick Trinity House pattern burner then is use. Cape Receiffe is also a Lloyd's signalling station, and is in telephonic communication with the Port Elizabeth Lighthouse. PORT ELIZABETH This lighthouse is situated in the middle of Donkins Reserve, Port Elizabeth, in latitude 33 degrees 57.7' S, longitude 25 degrees 37' E, the light having a range of 12 miles. The tower and lantern are octagonal in plan and are both of brickwork. The lantern glazing is of flat rectangular panes. Until 1903 the apparatus in use was a fourth order fixed lens, and a wick burner. In that year the old fixed light was superseded by a fourth order dioptric occulting light of 250 m/m focal radius, with a red arc flanking the white arc on either side. The optic consists of a diptric belt, 6 refracting rings and 9 reflecting prisms with an illuminated arc of 136 degrees, the remainder of the light being utilized for strengthening the red arcs by means of (1) a totally reflecting dioptric mirror of 250 m/m focal distance, subtending a vertical angle of 66 degrees and a total horizontal angle of 140 degrees, and (2) azumuthal or vertical condensing prisms in two sets carried to the full height of the apparatus. The characteristic of the light is 3 seconds eclipse every 10 seconds and is produced by means of a cylindrical aluminium shutter ascending and descending over the burner, the movement being obtained from an eccentric cam fitted to the driving machine. The occulting gear is clock-driven, the weights being suspended from a steel cable. The burners are of the incandescent oil vapour type with a mantle of 55 m/m diameter, the intensity of the beam being 12,500 candles. This station is in telephonic communication with Cape St Francis and Cape Receiffe Lighthouses and the Telephone Exchange of Port Elizabeth, and is manned by a lightkeeper and one assistant. Homing pigeons are kept here for use in maintaining communication with Bird Island Lighthouse. Meteorological observations are taken regularly and a time ball is dropped by an electrical apparatus released from the observatory. Ann anemometer is also fitted at this station. BIRD ISLAND This island near the Eastern limit of Algoa Bay was first provided with a light in 1852, when two wooden towers, each carrying a fixed light, were erected 18 feet apart. One light being 10 feet higher than the other, two lights whn in line gave a bearing over the Doddington Rock. One can easily picture the anxiety of the mariner on the look-out for these feeble lights in dirty weather. In 1873, a second order fixed diptric red light was erected on a massive square tower of masonry, and constituted a marked improvement upon the old lowe power double lights. But even this improvement ultimately failed to meet the demands of modern shipping, and constituted a marked improvement upon the old low power double shipping, and in 1893 the third light to be established on Bird Island was erected, an additional 25 feet height of masonry being added to the tower to give the light an increase elevation. The light has a range of 16 miles, the focal plane being 100 feet above high water, and is visible all round the horizon. The position of the light is latitude 33 degrees 50.4' S, longitude 26 degrees 17.2' E. The lanter, erected in 1893, has a cast iron murette and curved glazing in rectangular framing. The illuminating apparatus is dioptric and consists of a first order double flashing optic of 920 m/m focal radius, having 4 sides each subdivided and producing two white flashes of 3 seconds each. The characteristic of the light is as follows:-
The revolution of the optic is performed in 120 seconds and embraces 4 complete periods. The lens and table are carried on a set of vertical steel rollers guided by 2 sets of horizontal brass rollers. The power of the beam is at present 47,000 candles, but this will shortly be increased to 180, 000 candles by the introduction of incandescent oil vapour burners. The existing burners are of the 6-wick Trinity House Douglass type. The burner is fed by 2 fifty gallon Trinity House pattern pump lamps. Meteorological observations are recorded at this station, but the only communication with the mainland which is available at present is by the employment of homing pigeons. A relief tug with stores proceeds to Bird Island from Port Elizabeth once in each mouth. Emergency stores for shipwerecked mariners are kept in sealed drums at this station. GREAT FISH POINT This lighthouse is a comparatively recent erection, dating from 1898, when it was built to supersede the old fixed red light formerly exhibited at Port Alfred. As no shipping now enters or leaves the Port, the necessity for maintaining a light at Port Alfred ceases to exist. The light is situated on the crest of a sand hill about half a mile inland or northward of Great Fish Point, and about 2 miles from the mouth of the Great Fish River, in latitude 33 degrees 21.2' S, longitude 27 degrees 6.6' E. The light is visible over an arc of water. The tower is octagonally constructed of concrete and is about 30 feet high. The lantern has a cast iron murette and curved glazing. The optical apparatus is a first order dioptric single flashing bivalve of 920 m/m focal radius. One white flash of 2/5 seconds duration occurs every 10 seconds, the revolution being tons revolve over a bath of mercury. A set of horizontal brass guide rollers is provided as well as 3 vertical steel screwjacks for lifting the apparatus to enable the mercury bath to be cleaned. The light when first erected was fitted with a 6-wick Trinity House burner, giving a power of 145,000 candles to the beam. The burner was fed by means of two 12-gallon Chance pressure lamps. In 1908, the Author installed a vapourized oil burner with an incande4scent mantle of 85 m/m diameter, increasing the intensity of the beam to 600,000 candles and effecting a saving in cost of oil of œÀ120 per annum. The revolving apparatus is driven by clockwork, actuated by a set of weights suspended on a 9/16- inch chain and regulated by means of a "Sight" governor. It is fitted with a speed indicator and hand gear for turning the optic in case of derangement of the driving machine. HOOD POINT LIGHTHOUS This station was established in 1895, and is situated on the WEst Bank and near the mouth of the Buffalo River at East London in latitude 33 degrees 2.3' S, longitude 27 degrees 54' E. The tower is 32 feet in height from ground to balcony level and the focal plane of the apparatus is 180 feet above high water, giving the light a range of 20 miles with a visual arc of 174 degrees 22.5'. The lantern is circular in plan with a cast iron murette and curved glazing. The dome and ventilator arc of the usual modern type previously described. The dioptric apparatus is of the first order of 920 m/m focal distance, showing a group of four white flashes every 40 seconds as follows:-
The optic consists of 4 panels of lenses each lens subtending 45 degrees in azimuth, with a totally reflecting prismoidal mirror of 180 degrees and revolves over a mercury bath. An axialsteel shaft retains the revolving apparatus in true position, and two sets of ball bearings are provided to take the weight of the lens and table when the mercury is run off. The driving machine is weight driven and regulated by a"Slight" governor with speed indicator and hand turning gear for emergency use. The burners are of the Trinity House Douglass type with 5 wicks, the diameter of the outer wick being the same as that of the outer wick in the old 6-wick burner, and is fed by two 50-gallon Trinity House pressure reservoirs. An incandescent oil vapour burner will shortly replace the wick burner when the power of the light will be increased to 312,000 candles. Anemometer records are taken CAPE HERMES LIGHTHOUSE This station was built by the Author in 1906, and is situated on a headland at the entrance to the St John's or Umzimvubu River. It is the most northerly light on the coast of the Cape Colony. The focal plane of the light is 175 feet above high water and the range is 19 1/2 miles. The tower is octagonal and is built of a dark grey dolerite, quarried on the site. The lantern balcony is of concrete reinforced with old steel rails. The lantern is circular with a cast iron murette, vertical framing and curved glazing and surmounted by a single sheeted copper dome and modern ventilator. The dioptric apparatus is three sided of the fourth order and 250 m/m focal radius, exhibiting a single flashing white light. The lens revolves over a mercury bath and a set of upper and lower ball bearings is provided for sbusidiary use. Access to the inside of the float and bath is obtained by lowering the bath on a spirally grooved shaft which forms the pedestal. The driving clock is actuated by weights suspended on a steel cable and is regulated with the usual "Sight" governor, with dial speed indicator and emergency hand turning gear. The burner is of the incandescent oil vapour type with a mantle of 55 m/m diameter, giving a power to the beam of 30,000 candles. Considerable difficulty is experienced in dealing with extensive landslips which occur at the site of and along the approach road to the lighthouse. The formation of the hill in which the excavations for the foundation were made in loose gravel with huge dolerite boulders embedded therein. In heavy rain the loose material is coured out and a mud rush bringing enormous boulders with it, frequently results. In conclusion the Author would like to state that contrary to the opinion expressed by the public in connection with recent wrecks, the coast of Cape Colony with the exception of a few lights, is lit by a class of lighthouse that is quite up to the most modern types used in Europe. When the additions and improvements recommended by the Lighthouses Commission of 1906 have been carried out, the coast of Cape Colony will be as well lit as any coast in the world. CAPE COLONY - COAST LIGHTHOUSES, ETC.
|
STATION |
Year established or altered |
General Remarks: Description and Site of Lighthouse |
| Port Nolloth | 1909 | On Owners Island |
| Dassen Island | 1893 | Iron tower, red and white bands, on S. end of Island |
| Robben Island | 1865 | White tower on Minto Hill S. part of Island |
| Green Point | 1865 | Square tower on Green Point; 400 yards from low water |
| Cape Point | 1860 | Iron tower; white on on the point |
| Roman Rock | 1861 | Circular tower; red and white bands on S. Roman Rock |
| Point Green | 1895 | Octagonal tower; red and white sides |
| Cape L'Agulhas | 1910 | Circular tower; red and white bands on the point |
| Cape St Blaize | 1897 | Square white tower on the Cape; S. side of Mossel Bay. |
| Cape St Francis | 1906 | White circular tower on Seal Point; about 1 3/4 miles West of the Cape. |
| Cape Receiffe | 1890 | Octagonal tower with red and white bands on the point; W. side of Algoa Bay. |
| Port Elizabeth | 1903 | Octagonal tower on a hill, at back of town, adjoins Donkin Monument; painted white. |
| Bird Island | 1893 | Square stone tower near S. end of the Island E. Side of Algoa Bay. |
| Great Fish Point | 1898 | Octagonal tower; black and white sides; on hill 1/2 mile N. of point. |
| Hood Point (East London) | 1895 | Tower, chequered red and white; 1 mile S.W. of Buffalo River entrance. |
| Cape Hermes (Port St Johns) | 1904 | Octagonal grey stone tower; 44 feet high; on Cape; S. side of St John's River entrance. |