A century-old low-tech system continues to guide New Jersey’s Forest Fire Service
To spot these fires, the state uses a century-old system, which in an age of drones and artificial intelligence, Gerber said is remarkably effective.
Gerber’s tower office is dominated by a large circular wooden table that is about 4 feet in diameter. Glued on top of the table is a detailed map of the 20-mile radius that can be seen from the tower. Around the map are 360-degree compass readings. A taut string attached to a rotating metal ring and rifle scope, allows him to pinpoint the exact degree of a column of smoke.
This is called an alidade, the earliest of which was likely invented in the 4th century. A rifle scope is attached to spot the exact location of the smoke.
The entire contraption is called an Osborne fire finder, invented back in 1911. No electricity is required.
“So if [I] saw smoke, I would use this tool right here to pinpoint it, and I would get a degree reading out of 360 degrees of a circle, and I would call another fire tower and see if they could see the smoke and get their degree reading, and I’d use my map and we would cross it out like triangulation,” he said.
The tower is equipped with a landline telephone and a radio transmission system.
From the ceiling, he unlatches a wooden board, glued to it is a map of the entire state plotted with all 21 fire towers. Each tower is marked by a metal ring attached to a pulley.
“So I would use the crosshairs in the scope to pinpoint where the smoke is. I use this map right here and this would be Medford Fire Tower and then say this was, I was crossing a smoke with Apple Pie Fire Tower, we could pinpoint exactly where it is, where the X marks the spot of where the fire is.”