The construction site of the Armen lighthouse, 1867-1881

 

The island of Sein, located to the west of the Pointe du Raz at the western end of the Finistère department, extends further into the Atlantic Ocean by a series of reefs which extend nearly thirteen miles from the island. This line of pointed islets, or cornoc in Breton, of dangers and shoals is known as the Chaussée de Sein (ill. 1).

Drawing J.‑C. Fichou

This area is only passable in very good weather, favorable current conditions, and always with the help of experienced local sailors who can navigate the few narrow channels that cross it, marked by rare landmarks such as the Yann-ar-Gall, An-Namouic, and Neurlac'h rocks. In 1817, after six months of tireless work, hydrographic engineer Charles-François Beautemps-Beaupré produced a relatively accurate map of the area:

The large rocky plateau known as the Sein causeway is so dangerous, throughout its entire extent, that we can safely say that any navigator crossing it, without the help of a good pilot from the island of Sein, will owe their safety solely to a lucky accident.

This singular formation remained infamous in the minds of sailors, as countless ships were stranded or sunk on the causeway. The 1825 commission charged with preparing the report concerning the general lighting of the coasts of France decided to establish a light on the Pointe du Raz and another on the island of Sein to mark the direction of the causeway. It was also noted that it was not realistic to consider the construction of any beacon on the latter. Since one must never approach it, "it is necessary to be content, by placing lights suitable for avoiding this danger, to indicate by the relative position of these lights, whether those who see them are outside its limits on the north side and in the Iroise, or whether they are in the south on the side of the bay of Audierne. These two indications will tell them with certainty which way they must head to move away."

The Lighthouse, a Solution to the Dangers of the Sein Causeway

While sailors knew they had to keep a long distance from this luminous alignment to avoid running into the reefs, there was nothing to allow them to estimate the necessary distance out to sea. Moreover, in foggy weather, the insufficient ranges negated any assessment of the causeway's position. Shipwrecks, although reduced, continued, and complaints flooded the office of the Minister of Public Works. On the night of September 22-23, 1859, the Imperial Navy frigate, the Sané, sank on the Sein Causeway, intensifying the admirals' criticism. A solution to this problem had to be found and the approaches to the Narrows of Brest, a major military port in the West, secured. In April 1860, the lighthouse commission requested that the question be examined with the greatest care by the chief engineer of bridges and roads of Finistère. He was to draw up plans for the establishment of "a 3rd order lighthouse on the Pierres-Noires group at the entrance to Brest harbor and for a 1st order lighthouse near the end of the Sein causeway." Initially, it was planned to erect the light on the Madiou rock and, if it proved impossible to land there, another position was planned "less favorably located, but higher, more extensive and where the sea probably breaks with less violence... the Armen rock." To house the light and the keepers, it was planned to build a 45-meter high tower, divided into several floors so as to provide stores, a kitchen, three bedrooms and a service room. It was decided to follow the model of the Héaux-de-Bréhat lighthouse, built and lit on February 1, 1840, under the orders of engineer Léonce Reynaud (1803-1880), later appointed director of the lighthouse service.

This recommendation was approved on June 3, 1860, and the first field studies were to begin under the Parisian direction of Léonce Reynaud for the local commission composed of hydrographic engineers, civil engineers, and naval officers. Led by the chief engineer of Finistère, Maitrot de Varennes, this mission examined "the best arrangements to adopt for lighting the approaches to Brest." In July 1860, the members of the commission went to the Sein causeway aboard the aviso Le Souffleur and they studied in particular the low Madiou and Schomeur rocks, then the rocks of Neurlac'h and Ar-Men, a steep and small rock. Back in Brest, the engineer Maitrot wrote up his conclusions: "We must abandon the hope of establishing a large lighthouse on this point. The Neurlac'h rock offers the most favorable conditions." It appeared to all the observers of the place that construction in such an exposed location and on such a narrow, cramped reef remained impossible, so much so that the engineers proposed establishing the tower on a more withdrawn and larger rock, the Neurlac'h, located five miles from the end of the causeway. This solution was rejected by the commission, and especially by Léonce Reynaud, because it did not bring any significant improvement to the lighting of the place. The Navy was then asked to carry out a further in-depth hydrographic survey to find the best site.

Work had not yet begun when the creation of a transatlantic line between Le Havre and New York, with a stopover in Brest, was announced. It became even more urgent to resolve the problem of the causeway. The three landing attempts made in 1861, however, also ended in failure. Léonce Reynaud assessed the difficulties at their true value and decided to abandon the masonry tower project and to favor "something similar to the lighthouse at Pointe de Walde, with much greater height and less embankment." In this case, it would have been sufficient to drill seven holes to embed the posts intended to support the platform, even if the anchors had to be reinforced with cement masonry as the work progressed. The idea was quickly abandoned, however, because it was clear that a lighthouse with a metal structure would not have withstood the assaults of the sea in this location where only a masonry tower was feasible. The administration then decided to open a survey among the fishermen of the island of Sein, who had been consistently disdained until then, yet were "too practical in the locality not to have the most precise information, at least as far as the Ar-men rock was concerned." Accompanied by the island's mayor, the ordinary engineer Paul Joly, attempted to land in November 1865, but his attempt met with the same fate as the previous ones. Hope was somewhat revived during the summer after the lighthouse service anchored a large 185-ton lightship at Les Minquiers, off Saint-Malo, lit on September 25, 1865, and the 350-ton Rochebonne, off La Rochelle, lit on September 15, 1866. Couldn't the same thing be attempted on the causeway?

Regarding the lighting of the causeway itself, experiments were awaiting confirmation of the floating lighthouses to determine whether it would be possible to mount one at the end of the causeway; this solution would undoubtedly be the best, as the point on the causeway where a fixed lighthouse could be installed was already quite far from its end.

Finally, "the hope of solving the problem with a floating light" was also abandoned, due to the depths of 100 meters and the nature of the area, which was not conducive to good anchoring, since "a ship would not be able to withstand the violent jolts of the retaining chain for long and would even be at risk of sinking in the first storm."

Nevertheless, the Depot des Cartes et Plans resumed its mission in August 1866 under the direction of hydrographic engineer Alexandre-Edmond Ploix. The Navy participated in the operation and provided a steam-powered aviso to facilitate approaches to the rock. In an extremely rare event, the director of the lighthouse service traveled in person to Brest and boarded the Souffleur to assess the situation for himself. But this new attempt ended in the same way as the previous ones and did not provide all the desired information. It did, however, allow an opinion to be formed. The engineer Ploix reluctantly concluded that construction on Armen was possible, while specifying that "the establishment of a lighthouse on Ar-Men is an extremely difficult, almost impossible task; but perhaps it should be attempted given the vital importance of lighting the causeway." During the summer, Joly embarked again, but was at a loss. Finally, in August, the seafarers' representative of the island of Sein, Tymeur, managed to set foot on the rock and take a sample. We know that Armen is 7 to 8 meters wide and 12 to 15 meters long; that its surface is very uneven and that the summit only emerges 1.50 meters above the lowest spring tides. For the engineers of the lighthouse service, it was absolutely necessary "to repeat the experiment as often as possible and the Ar-men rock will finally emerge from the legendary state that previous explorations have made it appear to be." The decision was taken "to try the construction of a masonry massif on the Ar-Men rock" by giving it such dimensions that it could "become the base of either a stone tower or a sheet metal tower." Work could begin without knowing what the shapes and dimensions of the building would be.

An Exceptional Construction Site

On May 16, 1867, the government boat, the Armorique, left the port of Sein at 7:00 a.m.; "time spent on the rock, 15 minutes," noted Lacroix, the ship's manager, in his logbook. On July 7: "time spent on the rock, 45 minutes, return to port at 11:30 a.m." After seven dockings, the 1867 campaign ended: a total of eight hours spent on Armen to drill fifteen holes, 30 to 40 centimeters deep, intended to accommodate either the anchors to facilitate subsequent dockings or the iron dowels needed for the tower's foundations to secure the first courses of masonry to the rock. For this task, the island's sailors were called upon, as they were considered the only ones capable of maintaining their position on the reef. After "much hesitation, they agreed to carry out the holes requested of them on a fixed price basis and at a very high price," namely for 29,000 francs, or more than 500 francs per hole. And, to be sure that the task was accomplished, the administration signed contracts with the Sénan sailors and their representative, Chief Pilot Coquet. The workers, wearing espadrilles to avoid slipping, "were tied to the rock, a man watching the wave warned them each time and, despite these precautions, several were swept away." From time to time, a stronger wave swept across the site and the men found themselves in the water, kept afloat by cork life jackets, kindly provided by the administration. "It was a first step towards success." The following year, the Armorique anchored in the small port on April 8; Still under the direction of engineer Joly and conductor Lacroix, work resumed on the rock. Higher bonuses increased the ardor of the work and as the season was mild, sixteen landings were counted and 18 hours of time spent on the rock. Under these conditions, it was possible to carry out partial sloping and to drill thirty-four additional holes. "Their depth is 0 m 30, their diameter from 0 m 06 to 0 m 07. They cost on average 200 francs each. They constitute the preliminary operations among the attempts we are making to build a new lighthouse on the Sein causeway. »

Construction itself began in May 1869 under the direction of a new engineer, Alfred Cahen, appointed to his first post in Brest in May 1867. Galvanized iron dowels, 1 meter long and 6 centimeters square, were driven into the holes drilled during the two previous campaigns, and the first small-scale gneiss rubble from the island of Sein was then laid, sealed with pure Portland cement, mixed on site with seawater. By the end of the 1869 campaign, after 24 successful dockings and 44 hours spent on the rock, 25 cubic meters of masonry had been completed (Fig. 2).

Fig. 2: Elevation and section of the lighthouse structure on Armen Rock in October 1869

Drawing J.‑C. Fichou

It was an unexpected success, but everyone wondered if the masonry would withstand the harsh winter weather. The massif was found intact the following year and the team of sailors from Senan dug the circular recess necessary to establish the first course of facing in Kersanton rubble, at the time the best building stone. But there was concern about the slow pace of the work and the real chances of success; the lighthouse commission was worried, the admirals were worried, especially Admiral Paris and Admiral Jurien de la Gravière, successive directors of the map and plan repository; the general directorate of bridges was worried, because the sums spent – ​​then more than 52,000 francs – were not in proportion to the cube of masonry. Never before had a construction of this kind cost so much. As the first foundations pointed to the rock, Léonce Reynaud took it upon himself to convince them, because there was no question of giving up; the director wanted to see this lighthouse built and "he would like to crown his career with it." A new setback occurred when the country entered the war against Prussia: the truncated campaign of 1870, "which was not pursued with the same ardor," only allowed eight landings for nineteen hours on the rock and 11.55 m3 of masonry. That of 1871 was hardly more brilliant with twelve landings and twenty-two hours on the rock, but it should be noted that it still took place, a real feat given the chaotic situation in the country. While the masonry massif was practically completed, the question of the tower then arose, and more particularly its height. As the base's usable surface area was limited, it was decided to abandon the original 40- to 45-meter structure planned for the project: "the oscillations to which it would be exposed by strong winds could compromise its stability, given the small diameter of its base." Under these conditions, the commission set the height of the lighthouse at approximately 30 meters above high tide (Fig. 3).

Fig. 3: Stages of construction of the Armen Lighthouse, 1869-1877

Drawing J.-C. Fichou

The bridge engineers, and more particularly Léonce Reynaud, took a dangerous gamble in this circumstance, because they were well aware of the harshness of the sea at the end of the causeway and they nevertheless estimated that a tower with foundations narrower than those of all the other sea lighthouses already built could withstand it. For structures of this nature, engineers at the time were content to compare them with similar buildings and to design them with equal or greater stability. Engineer Mengin, in charge of the initial studies, simply admitted that "in general, we can say that resistance calculations are little more than a means of transferring to a specific structure the experimental results provided by other similar structures. However, nothing can be concluded from the comparison of the Armen lighthouse with the other existing sea lighthouses since the latter are all in conditions of much greater stability." The Parisian management could not be satisfied with such references and asked for some additional arguments, which our engineer provided. For him, the study of the calculation of the stability of this tower at sea was of only secondary interest due to the uncertainty in which he found himself "on the main data of the problem: nature and intensity of the force of the blades, elasticity of the masonry, influence of oscillations, etc., uncertainty which removes all precision from the results obtained." The commission was satisfied with this because the science of the resistance of materials remained in its infancy and for the tower of Armen it was admitted that no study would be carried out because "in the absence of any precise data on the action of the blades, on those of the wind, on the resistance of the masonry to traction, etc., it was not possible to obtain any mathematically established result." However, by comparing the rare data of Armen with the French or foreign towers of the same order, we see that the lighthouse is very slender, especially to face the swells of the Atlantic. The stone is very small, barely 0.036, and the base cannot have the traditional wheelbase.

In the words of director Léonce Reynaud, we always try to "make it heavy," and this simple precaution is worth an engineering theorem. It was therefore decided to stick to the system followed in the construction of the turrets, using blocking masonry reinforced with galvanized iron crampons in order to obtain "thanks to the energy of the cements available today, monolithic masses superior in strength to what was previously achieved using heavy cross-cut stones." All these stones come from the Kersanton quarries, in Brest harbor, which provide a material of remarkable quality, highly prized by civil engineers. It is a rare, extremely resistant eruptive rock, with a very fine, homogeneous, bluish-gray grain. The crownings, steps, and opening frames are all made of cut stone, the largest of which weighs 600 kilos. Each year, a tender was opened, and the four owners of the Loperhet quarries responded to the administration's wishes. The stones were prepared in successive courses and presented to the Brest marking park, where they were arranged in their actual configuration to assess the size and value of the materials delivered. For the year 1876, Mr. Poilleu, known above all for his skills as a funerary sculptor, won the contract. He was to deliver approximately 40 m3 of cut stone, 40 m3 of rubble for the facing, and 20 m3 of blocking rubble. The products "will be of the highest quality, perfectly free from quarry crusts and any defect detrimental to their durability and appearance, with a uniform blue or gray grain." The rest of the masonry is made of rubble that a single man can handle without difficulty. The mortar is composed of Portland cements from the English firms Knight, Bevan and Sturge, then Demarle & Lonquety from Boulogne. The cements were used pure, less to increase adhesion than to activate the setting, which remained essential, especially during the first campaigns. "All in all, and taking into account the precautions taken in the construction, the engineers have full confidence in the solidity of the lighthouse; it is clear, however, that we are at the limit here and this is what prevented us from giving the lighthouse a greater height than we would have wanted."

In May 1871, the driver Lacroix retired and was replaced by a young and spirited 25-year-old agent, Probesteau, who went on to have a brilliant career. At the end of May 1874, Alfred Cahen left Finistère for Épinal to be closer to his native Lorraine, which was now in German hands. He was replaced by the ordinary engineer Mengin-Lecreulx, then stationed in the ordinary service of the Morlaix district, but who was well-versed in the problems of offshore construction. The shipyard's workforce grew as the work progressed, and by 1878, it numbered fifty-five people, including the skipper of the Armorique, two stokers, four pilots, and thirteen sailors. Eight masons, five stonemasons, two carpenters, a blacksmith, and around twenty laborers completed the staff.

At the end of the 1875 campaign, the masonry towered three meters above the most prominent head of the rock, and the highest spring tide level was exceeded. However, the meteorological elements never allowed for the quality and quantity of the work to be predicted in advance. The 1877 campaign, for example, began under inauspicious circumstances:

Since the beginning of the campaign, the almost constantly rough seas had long been unfavorable to the work at Ar-Men, which progressed little. Until the 15th of this month, the date of my last precise information, only six boats had docked on May 8, 25, and 26, and on June 9, 10, and 14, a total of six. The first three tides were mainly devoted to installing the cladding. From May 26 to June 9, the sea was very rough, and almost the entire tide of June 9 had to be used to repair the damage caused by the sea. […] The results were mediocre, but a good month would be enough to largely make up for the lost time.

The dangers remained numerous. On June 9, 1878, the boat carrying thirteen masons and the driver capsized under the influence of a more powerful wave, and it was "only thanks to the dedication and energy of Mr. Probesteau, as well as Captain Fouquet of the steamship Armorique, that there were no fatalities to be deplored." Under these circumstances, the Chief Engineer proposes, on the one hand, to award each of the thirteen workers who were thrown into the sea a gratuity of 30 francs... and, on the other hand, to send an official token of appreciation to Mr. Probesteau, the driver, who personally saved two of his men. The work became even more complicated as the Parker-Médina cement, which had been spoiled during the first three campaigns, was showing significant discoloration, and all the joints in the lower courses were deeply hollowed out, threatening the entire structure. Not only did the workers continue to lay the ashlars for the tower's upper courses, but they also had to simultaneously reinforce the lower section with stronger cement.

This was a real construction feat, of which the bridge engineers were well aware; the affair received considerable media coverage at the time, and numerous articles in Parisian newspapers reported on the progress of the construction site. The difficulties were far from being completely resolved and, "despite the zeal and ardor shown by the personnel," the 1879 campaign was catastrophic due to the appalling weather. By the end of September, when the worksite was closed, the masonry had only been accessed nine times and "effective work could only be done seven times." Taking advantage of the exceptional weather, the team leader decided to extend the work and managed to return to the lighthouse for three additional days in October. The news quickly spread around the world and highlighted the interest abroad in the construction of the lighthouse. On this occasion, the director of the Lighthouse Service, Allard, shared the message written by the secretary of the equivalent American service:

The Lighthouse Board, having learned of the great difficulties successfully overcome in the construction of the lighthouse on the Ar-men Rock on the Île de Sein, would be very eager to examine the drawings for this important work... the civilized world owes its thanks to France for this arduous and important success for navigation.

By 1880, the bulk of the work was completed: on July 17, workers were laying the last stones of the lantern wall. After August 12, six masons were permanently installed in the tower to build the vaults of the upper floors and lay the window frames: "We can now say that this impossible feat has been achieved, after twelve years of effort, and the lighting of the Ar-Men lighthouse is now assured in the near future." » Indeed, the light was first lit for testing on February 18, 1881, almost a year to the day after the death of its designer, Léonce Reynaud, on February 14, 1880 (Fig. 4).

Fig. 4: Elevation of the Armen lighthouse in 1881

Drawing J.-C. Fichou

The interior fittings, however, were still very rudimentary. In fact, the tender for the joinery, doors, windows, paneling, and parquet flooring was not awarded until November 17, 1880, and installation work did not begin until May 1881. On August 31, the official inauguration was supposed to conclude the most perilous and prestigious construction operation carried out by the Lighthouse Service, but it was still necessary to improve the reception of the keepers, so much so that the bill exceeded the amounts granted in 1875. The 900,000 francs planned at that date were no longer sufficient for completion; a ministerial decision granted an additional 10,000 francs in August 1881, then another 20,000 francs in December of the same year. By the end of the 1882 campaign, more than 940,000 francs had been spent to complete the project, or so it was thought at the time.

With what result?

The adventure ended after more than fifteen years of effort without any notable accidents, and the director was able to congratulate himself that the work had "to date caused neither death nor serious injury." However, the construction site, which had experienced so many difficulties, with multiple capsizing and sinking of lifeboats, experienced its most tragic event after the lighting: on June 24, 1881, a team of masons was approaching the tower to carry out the final interior fittings when a wave struck the lifeboat and threw two men overboard, including Alain Riou, who was later killed. The tower's cramped dimensions gave rise to another rather serious difficulty: accommodating all the objects and materials necessary for the service: furniture, tools, landing and rescue equipment, food, oils, and fuels for heating and feeding the fire. At the sight of this narrow column "placed in the middle of the ocean as far as the eye can see from the land, in terrible surroundings, with these rooms barely seven square meters, one cannot help but think of the life the keepers would lead, often deprived for days, perhaps for months, of any communication with the land." The administration, however, managed without difficulty to recruit the four men needed to keep the fire going: Alain Menou, Jules Vénec, Germain Fouquet, and Michel Le Noret. Over time, they noticed, not without concern, that the cement in the tower's foundations seemed to be loosening.

The waves and salt water were undermining the lower foundations, and the lighthouse service engineers were alarmed. During the summer of 1887, an initial investigation was carried out, but for the Brest engineer, the whole thing remained solid: according to him, the "mortars at the base were holding up." However, it was decided in 1896 to reinforce the base of the building to combat the effect of the waves, even though "the resistance of pure cements to decomposition by seawater is not known." So why make such a decision when nothing worrying had been revealed? No doubt because the collapse of the beacon towers of Men-Hir in 1886, of Fourches in 1895 and of Petit-Charpentier in 1896, swept away without warning signs, called for caution and the need for "reinforcement work", because "we cannot abstain and resign ourselves to running the risk of a catastrophe which would cost the lives of the keepers and which would seriously compromise the reputation of the Lighthouse service in France and abroad". The threat of the quick-setting cement coming loose and the insufficient mass of the tower were resolved by creating a protective cement envelope 50 cm thick and more than 11 m high. Thus, to reduce the vibrations clearly felt by the guards, and in "the doubt", the maritime services of Brest undertook the work, because it was important to begin the consolidation "all the more so since no apparent incident could reveal the imminence of an accident". On May 21, a ministerial decision approved the work and granted a sum of 100,000 francs for its completion; on October 4, 1900, the total sum was increased to 130,000 francs, then to 150,000 francs on August 27, 1901, the year of the completion of the protective berm.

More than 1.15 million francs were spent to see the tower erected on the causeway and maintain it to this day; stat virtute Dei et sudore populi. From that time on, the feat went beyond the inner circle of civil engineers and entered the public domain. The tower, erected in such inhospitable places, is a symbol of humanity's victorious struggle, of human will and cooperation against the elements at the end of the 19th century, when science had yet to prove all these benefits. The challenge taken up by Léonce Reynaud, to which islanders, sailors, fishermen, and builders cling, was mastered in the face of the indomitable forces of nature and the sea.

On April 10, 1990, the last two guardians definitively left the tower, which today has become a sentinel without a man and of little use for navigation. It is now nothing more than the fruit of human will, while the legend grows stronger every moment. The question of preserving this monument then arises, and opinions are very divided on the subject. Should we invest significant sums, which the Ministry of Culture does not have, to maintain this tower on the Sein causeway, or should we resign ourselves to seeing it disappear under the blows of a wave more powerful than the others? To the extent that Reynaud himself considered himself satisfied if Armen held for more than a hundred years on the beaten rock, we can admit that the deadline has passed and that the inevitable fate of lighthouses at sea is to collapse.

Summary of the Armen lighthouse construction site.

Author

Jean-Christophe Fichou

Jean-Christophe Fichou, a history professor with a doctorate in geography and history, and accredited to supervise research, has worked for many years on the maritime heritage of the French coasts. He has been an associate researcher at UPRES-A, CRHISCO, University of Rennes II, and CERHIO-SOLITO in Lorient, and is a research member of CETMA, CNRS-MNHN (Center for Ethnotechnology in Aquatic Environments-National Museum of Natural History). He is a member of the National Commission for the Preservation of French Lighthouses. He is the author of numerous articles on the history of maritime signaling and, in 1999, with N. Le Hénaff and X. Mével, published Phares, histoire de la signalisation maritime des côtes de France à Douarnenez (Lighthouses, History of Maritime Signaling on the Coasts of France in Douarnenez) with Éditions de l’Estran, a work awarded the Concarneau Maritime Show Prize and the Académie de Marine Prize. He also published a book on Lighthouse Keepers, 1798-1939, with the Rennes University Press in 2002 and received the Marine Academy Prize for the second time in 2007 for his book written with F. Dreyer, The History of All the Lighthouses of France, published in 2005 in Rennes by Ouest-France. Four other of his works are in press: The Fleet of the Lighthouse Service. Douarnenez, Glénat - Chasse-Marée; The Canneries of Atlantic Brittany. Plomelin, Éditions Palantines; Fisheries and Breton Fishermen during the Second World War and in collaboration with P. Arzel, A. Geistdoerfer, O. Levasseur, J. Matras-Guin, Anthropological and Historical Studies of Maritime Fishing Techniques, from the Modern Era to the Present Day - Normandy, Brittany, Vendée.