Difficulties in Surveying Lighthouse Locations

The process of surveying a lighthouse location is often fraught with delays and requires immense patience^[1]. Weeks may be spent in reconnoitering the position, awaiting a favorable wind and a placid sea^[1]. Time to the surveyor must be no object, as he is the sport of the elements, and he must curb his impatience^[1]. The actual operations on the rock may only occupy twenty minutes or so, but the task of landing is equaled by that of getting off again, the latter frequently a more hazardous job than the former^[1].

The west coast of Scotland is particularly dreaded by engineers due to the caprices of the ocean, leading to bitter disappointments and maddening delays^[1]. This is attributed to the coastline's 'cruel, forbidding character' and its exposure to the full reach of the Atlantic, characterized by a puzzling swell and vicious currents^[1]. The same challenges apply to the west coast of Ireland and the open parts of the South of England^[1].

The Casquets, off the coast of Alderney, exemplify the difficulties in approaching certain lighthouse sites, as they are washed on all sides by wild races of water^[1]. There is only one little cove where a landing may be effected by stepping directly from a boat, and this place can be approached only in the calmest weather and when the wind is blowing in a certain direction^[1]. The author of the source notes having 'frittered away three weeks in Alderney awaiting a favorable opportunity to go out, and then gave up the attempt in disgust'^[1].

The construction of the Tillamook lighthouse on the Oregon coast was marked by extreme difficulty and peril^[1]. The engineer in charge of the survey was compelled to wait six months before he could venture to approach the island^[1]. Even after this wait, attempts to land were repeatedly thwarted by treacherous swells and curling waves^[1]. In one instance, two sailors who managed to jump ashore were forced to retreat due to the increasing swell^[1].

Further attempts to survey the rock led to more dramatic setbacks. The engineer himself managed to run a line from point to point, but this was done hastily and under significant risk^[1]. A subsequent attempt to make a more detailed survey resulted in tragedy when an experienced master-mason of Portland, Mr. John R. Trewavas, was swept into the sea and never seen again^[1]. This fatality stirred the public to such a pitch that the authorities were frantically urged to abandon the project of lighting the Tillamook^[1].

The challenges of surveying lighthouse locations sometimes demand unconventional solutions^[1]. David Stevenson recounted an experience where he and his brother, while surveying a rock off the west coast of Scotland, had to remove their boots and proceed in their stockinged feet due to the slippery, seaweed-covered surface^[1]. Despite the discomfort of their 'toes display[ing] an uncanny readiness to find every needle-point on the islet,' they managed to complete the survey^[1].

On a wave-swept rock, the preparation of foundations is generally not overly complex^[1]. The sea's relentless erosion typically leaves a solid surface, making it an excellent base for the superstructure^[1]. The engineer often takes the exposed surface of the rock as the basis for the work^[1]. However, when the beacon is to be erected upon a sandy bottom, the engineer's work becomes more baffling, as he is compelled to carry his underwater work down to a point where a stable foundation may be secured^[1].