Even with limited technology in 1937, there was an aerial reconnaissance flight that had identified spots back along Trail Ridge and higher up on top of the mountain. The Recon Flight never noticed a "spot" developing in the bottom of Clayton Gulch below the crews building line. Given the fire's origin was a lightning struck tree that was produced by a passing lightning storm, could this passing storm have produced more than one strike in the area?? If so, could have the strike remained undetected until winds were in alignment to increase the fire behavior…remember previous winds were from the southwest, the "spot" is sheltered from these winds in the bottom of the drainage below. The passage of a dry cold front switched the winds to the northwest. When dealing with spots typically one looks in the predominate direction of the wind as to where they might be found (e.g. downwind). The documentation of the event describes the spots on Trail Ridge as within 100 feet of the main perimeter. One probably wasn't looking ¼ to ½ mile away for a spot. Today as we fight fire in lightning prone areas, are we looking for the "sleeper" that may be established in a site that could, given optimal conditions, come to life in a hurry and cause a similar situation?