Wolf House Fire Findings

(as published in "The Moon Letter", July 1996 issue)

The following summarizes the findings of a report submitted by fire investigation team led by Bob Anderson, a noted California forensics expert.

With the intent to examine the remains of the Wolf House for any clues as to the cause of fire, a multi-disciplinary team of ten experts in fire investigation met in Glen Ellen in May 1995 and spent four days going through the remains of what once was a magnificent 15,000 square foot structure.

Pieces of charred wood timbers remaining in the notched masonry pockets where beams connected to the stone walls were studied to determine the most likely progression of the fire. The timbers in the dining room were burnt more severely than in the other rooms. From these clues, the area of origin appeared to be in the dining area located on the ground floor under the library and study. The remaining timbers in the pockets in the adjacent grand living room were canted and showed signs that they had failed first by the force of the tile roof dropping down and then subsequently they were charred by the fire.

The dining room had the only fireplace finished with wood in the house. The eight other fireplaces were finished in stone. The significance appears to be that workman were applying finishing oils to the wood the day of the fire.

A complete review of the design and construction documents; witnesses statements and historical records were considered, along with a computer recreation of the structure, in order to determine the most probable cause of the fire.

Although arson can not be completely ruled out, it is low on the probability list as the dining area would not be the natural choice for an arsonist, nor would an arsonist be content with a single place of origin. In addition, the site was so remote that traveling to the house after dark would have required a lantern (easily observed from the London ranch house) or risk breaking their neck.

August 22, 1913, was a typically hot and calm California night. This ruled out lightning as a cause.

Building plans showed a telephone system, but there was no evidence that the system had been installed.

The house was wired for electricity as evidenced by electrical junction boxes, conduit embedded in the walls, copper wire, old knob and tube porcelain insulators, and an electrical plan, however it does not appear that the system was connected to a generator.

There are several factors that strongly suggest linseed-oil stained rags as being the culprit. There were no furnishings in the house at the time of the fire, yet it was known that the cabinetry was being finished the day of the fire. Even though there are few details of the interior finish, the local Santa Rosa Press Democrat newspaper reported that the extent and quality of the walnut and oak interiors were magnificent. We know that Jack's insistence on natural products and natural finishes would demand linseed-oil based stains and varnishes, as these were the "industry standards" for fine woods, as they had been for centuries. The most likely area of origin for the fire has been identified as the kitchen or dining area on the ground floor of the west wing. This and the library on the floor above would be precisely the areas where these finishes would be used in greatest amounts. The hazards of careless disposal were known to the wood finishes of the age, but knowing of a hazard does not imply elimination of it.

Prior to flaming ignition, the self heating process of linseed soil on cotton releases large quantities of dense white smoke with a choking, lachrymatory effect, apparently as a result of alkehydes (hexanal, heptanal, etc.) being generated. This smoke is readily detected by a person in the vicinity or by modern smoke detection systems. In the Wolf House, everyone was gone, and there obviously was no smoke detection system. A loosely piled handful of cotton rags dampened with boiled linseed oil has been shown by our experiments to be capable of self-heating to flaming ignition in a few hours.

The final key is temperature, however. We know that the higher the ambient temperature, the lower the heat losses to the surroundings will be, and the faster the oxidation reaction will occur. The one striking observation of London's neighbor was that the night of the fire was the hottest night in memory, thus possibly providing just the one extra factor to enhance ignition. The flaming fire created by even a modest pile of linseed oiled rags can be sustained as a very energetic fire for more than an hour. This is surely enough heat and time to ensure the ignition of any wooden shelves or cabinetry is close proximity. The time factor is correct. Workmen reportedly left by 6 p.m.; Jack may have visited there early in the evening, prior to smoke being detected.

Jack London State Historic Park

"Effective June 1, Jack London State Historic Park will be closed on Tuesdays and Wednesdays. The park is scheduled to be permanently closed by July 1, 2012."

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