Thimble Shoal Lighthouse

 lighthouse, foghorn, NRHP - National Register of Historic Places

At the entrance to the vital waterways of Hampton Roads, there are two parallel sandbars named Wiloughby’s Spit and Horseshoe Bar. For many years vessels navigating this highly trafficked area were warned of the bars by lightships, but by 1859 the Lighthouse Board had become enamored with screwpile designs, which are literally screwed directly into the seabed. Wherever possible, the Lighthouse Board replaced the floating light vessels with these new permanent lighthouses, which were much less costly to maintain and staff.
The “thimble” of Horseshoe Bar was chosen as the site of the new structure. This location was buffeted by strong easterly winds, so the Board took measures to ensure the stability of the lighthouse with a screwpile foundation of extraordinary strength surrounded by a generous amount of riprap. Construction began in the spring of 1872, and the fine, compact sand of the bars proved troublesome to the process of screwing in the piles. Work was delayed when a cast-iron column used for a “follower” on a pile broke and when one of the screws snapped because of defective casting.

On October 15, 1872, the light was shown for the first time, officially replacing the last remaining lightship in the district. The Thimble Shoal Lighthouse, which exhibited a fixed white light varied by red and white flashes, was a mere three and half miles away from the Old Point Comfort Lighthouse. The screwpile foundation was built in eleven feet of water, and was topped by a hexagonal cottage with the lantern protruding from its roof. This very ornamental lighthouse was destroyed in a fire of unknown origin on October 30, 1880, thus beginning a long and surprisingly regular succession of disasters at Thimble Shoal.

Given the importance of navigating the dangerous sandbars, the replacement of the lighthouse took priority over other projects in the district. A new lighthouse intended for Bell’s Rock in Virginia had just been completed, and it was decided to place it at Thimble Shoal instead. The screwpile foundation of the former light could be reused, and divers further aided the rebuilding effort by recovering various pieces of the old structure, including the water tanks, boat davits and portions of the lantern and lens.

On December 6, the lighthouse tender Tulip, with the necessary material and a construction crew on board, braved severe, icy storms to re-establish the light. Owing to the quick work of everyone involved, the light was re-shown on December 24, having been out of commission a mere fifty-five days. The new light was produced by a fourth-order Fresnel lens, with a focal plane of forty-two feet and a visibility threshold of twelve miles. Two fog bells were simultaneously sounded every five seconds when visibility was limited.

The path between the sandbars marked by Thimble Shoal lighthouse is difficult to navigate, especially in adverse weather conditions. This was evidenced by a series of collisions beginning in 1891, when a steamer struck the lighthouse. Just seven years later, an errant coal barge hit it too, resulting in considerable damage noted in the Lighthouse Board’s report: “The entire lower gallery on the southeast side was carried away and the two adjoining sides were damaged. All the joists in the southeast section were broken and thrust out of position. ...Other parts of the ironworks suffered, and the house was lifted about one half inch off the radial beams.”

In December of 1909, the lighthouse was rammed one more time, and this disaster proved to be its undoing. The schooner Malcolm Baxter, Jr had just entered the bay from the stormy Atlantic, under tow by the tug John Twohy. Passage by Thimble Shoal was treacherous, as snow flurries and strong gales frustrated the ships’ efforts to maintain a straight course. While the Baxter strained against the towline, it suddenly lost its steering capacity. The Baxter communicated this information to the tug, but the tug’s crew had already released the towline. With no means of control, the crew on the schooner watched helplessly as the errant schooner slammed into Thimble Shoal Lighthouse, causing the floor of the structure to give way. The station’s stove was overturned, spilling its burning coals onto the wooden structure and igniting a calamitous fire. The keepers escaped by boat, as the Baxter repeatedly rammed the lighthouse and was itself in danger of catching fire. Finally, the Baxter drifted free of the lighthouse, and the tug was able to rescue the keepers and place the schooner under tow once more.

This latest fiery disaster must have convinced the Lighthouse Board to alter the design of the Thimble Shoal Lighthouse as five years later a nearly fireproof, cast-iron tower with a caisson foundation was placed at the shoal. The enormous caisson was towed to the new site, which was located only a few feet from the screwpile foundation on which a temporary light had been established. After dredging part of the shoal, the caisson was sunk into position and then filled with concrete.

The top of the new iron lighthouse stands 55-feet above sea level, and originally housed a lens manufactured by Barbier, Benard and Turenne of Paris, France. The lens consisted of six panels that revolved on ball bearings to produce a characteristic of fixed white for one second, and eclipse for one second. The occultations were achieved by covering alternate panels with spherical mirrors that intensified the light in the opposite panel. A five-foot long diaphone horn was used as a fog signal, but a bronze bell cast at Baltimore in 1900 was kept on hand for emergencies. The tower possesses unusual porthole windows and is topped by a circular lantern fitted with curved panes in a diamond pattern. The lantern is seven feet in diameter and is topped by a ventilator ball along with a bronze lightning rod with a platinum tip. Concrete cisterns in the caisson foundation provided a fresh supply of water for the keepers until 1964, when the light was fully automated.

For the next 20 years, the lighthouse was powered by 80-pound lead acid batteries, which were dangerous to land at the station. The electrical source was converted to solar in 1986, when four 35-watt panels were installed. In 1988, the tender Red Cedar, accompanied by a 100-foot barge, brought a forty-man crew to refurbish the lighthouse. Thimble Shoal was one of seven structures scheduled for repairs that year, and owing to its exposed and wind swept location, was the one most in need of attention. The walls, inside and out, were chipped and repainted a brownish-red.

A 1993 inspection found that part of the main concrete deck was missing, and that other parts contained small cracks. The inspectors recommended that the lighthouse be painted bright red in order to aid “mariner discernment” of the structure as a daymark. They also suggested that the glass of the lantern panes be replaced with ultraviolet-stabilized acrylic panes, in order to combat the effects of sun damage. Finally, they recommended removing the twisted remains of the old screwpile light.

On August 22, 2005 at 9:00 a.m. EDT, an online auction was opened for the Thimble Shoal Lighthouse along with three other offshore lighthouses of Virginia. Interested bidders were required to give a $5,000 deposit to the General Services Administration and were allowed to tour the lighthouses on September 20th and 21st. The invitation for bids informed interested parties that 1) the lighthouse would need to be maintained according to the Secretary of Interior’s Standards for Rehabilitation, 2) the right of ingress and egress would be retained by the Coast Guard to operate, repair, replace, or relocate the aid to navigation located at the property, and 3) lead-based paint and asbestos might be present at the lighthouse. Peter Jurewicz of Smithfield, Virginia, who had always wanted to visit the lighthouse, submitted the winning bid of $65,000 on October 5th. He is looking forward to the “adventure” of restoring the structure, which will be just the latest chapter in the adventurous life of the Thimble Shoal Lighthouse.

References

Bay Beacons, Turbyville, 1995.
"Thimble Shoal Light Station's National Register of Historic Places Nomination."
The Keeper’s Log, Winter, 1997.

Location: Located 3.5 miles west northwest of Fort Monroe.
Latitude: 37.0145
Longitude: -76.2404