Revealing the Second Boat of Pharaoh Khufu by Remote Sensing
Principal Investigators: Dr. Farouk El-Baz
Collaborators: Claude E. Petrone, Photographic Special Projects Manager, National Geographic Society
Sponsor: Black & Decker Corporation (Robert Moores, Product Development Coordination)
This project involved the nondestructive investigation of a boat pit of Pharaoh Khufu. The pit in question was located in 1954, aligned with another one, 18 meters south of the Great Pyramid of Giza. During the same year the eastern pit was excavated from under a cap of 41 limestone blocks and found to contain a disassembled boat. The disassembled boat was made of cedar wood 4,600 years ago. The wood was excavated, and the assembled vessel was placed on exhibit at the Boat Museum, which was built on the site of the discovery. By 1986, however, the boat had shrunk about 0.5 meters since it was assembled in 1966. It was feared that such deterioration may have been caused by the changing environmental conditions inside the museum.
Since the second (western) pit was thought also to contain a boat, it was hoped that the investigation of its environmental surroundings would lead to a better understanding of how best to preserve the ancient wood. This idea was the driving force behind the project. A research plan was developed through an agreement between the EAO and the National Geographic Society to undertake the following steps:
- Geophysically surveying the site
- Drilling a nine-centimeter hole by means of dry rotary drill motion through the limestone cap rock; the drilling and other operations were sealed by an air lock to separate the air inside from that outside
- Sampling the air in the cavity at different levels
- Measuring pressure, temperature, and relative humidity inside the chamber
- Photographing the interior with a video camera using a fiber-optic “cold” light and a 35-millimeter still camera
- Sealing the drill hole with material similar to that used by the ancient Egyptian builders.
When the testing of the equipment was completed, site investigation was conducted during October 1987. First, a scaffold was built on top of the selected site, and a tent was set up to protect the imaging equipment. Then one of the block of the limestone cap rock was selected and prepared for drilling. The block was 160 centimeters thick, and there appeared to be no change in pressure as the drill bit went through it. This indicated that there may have been communication between the atmosphere inside and that outside the chamber. Seventy liters of air were collected from 18 centimeters, 94 centimeters, and 145 centimeters below the ceiling for analysis by specialists of the National Oceanic and Atmospheric Administration (NOAA) at Boulder, Colorado.
Photography of the interior revealed a disassembled boat. Much like the one that was opened in 1954, the second pit contained stacks of wood with pieces of the cabin arranged on top. This second boat appeared to be smaller than the first and had four small pointed oars. The pressure inside the chamber was identical to that outside. The temperature measured 27 degrees C (81 degrees F), and the relative humidity was 85%.
As the air samples reached the NOAA’s laboratories, atmospheric scientists and physicists began to monitor the contents of the canisters and analyze their components. Results of freon analyses came first; freon-11 measured 300 parts per trillion, and freon-12 about 540 parts per trillion. These values were higher than, but close to, those of the air measured near Cairo.
An unusually high value was that of the content of carbon dioxide, which measured 720 parts per million, double the amount in the surrounding atmosphere. Carbon dioxide might have been produced by degassing from the organic materials inside the pit or even by being driven off the limestone walls of the chamber. A test to date the carbon dioxide gave an age of 2,000 years. This indicated that it was a mixture of ancient air and a modern counterpart.
Three attempts were made to capture from the air organic particles to identify any bacteria or pollen. These samples were completely free of microbial contaminants. This may have been the case because the air was pumped from nearly one meter above the contents of the chamber, whereas bacteria or other organisms may have settled at the bottom of the pit or the upper surface of the wood.
Thus, at both sites “video” archaeology was able to aid in the study of delicate artifacts without harming them or affecting their environment. The success of the two projects convincingly established the worldwide applications of remote-sensing technology to archaeological investigations.
• Finding a Pharoah’s Funeral Bark. National Geographic, Vol. 173, No. 4, April 1988, Washington, D. C. p. 512-533. (1988)
Digital copy unavailable.
• In Search of Pharaoh’s Ship. The Explorers Journal, Vol. 66, No. 3, September 1988, p. 108-113. (1988)
Direct link to PDF copy: http://www.bu.edu/remotesensing/files/pdf/340.pdf