When the first sawmills were established, they were small water-powered facilities that were usually located near the timber source and, when the forests were cleared, could be converted into grinder mills after farming was established. Later, larger circular sawmills were developed in the lower reaches of a river and the logs were floated towards them by log drivers. [2] In the wider, slower sections of a river, logs can be tied together in wooden rafts. [3] Rafts could not cross the smaller, wilder sections of a river, so individual logs were driven down the river like large cattle herds. Timmerflottning started in the 16th century in Sweden and in the 17th century (tukinuitto) in Finland. [4] The total length of wooden floating routes in Finland was 40,000 km. [4]

Billet jam in Berlin, New Hampshire.
The log drive was a step in the process of building a larger lumber in remote locations. In a place of snowy winters, the annual process typically started in the fall, when a small team of men carried vehicles upstream of the lumber-lined area, cut an opening and built raw buildings for a log camp. [5] In winter, when things were frozen, a larger team moved to the camp and began cutting down trees, splitting trunks into 5 meters (16 ft) long, and transporting the logs with oxen or horses over icy paths to the riverbank. There, the logs were placed on "rolling paths". In the spring, when the snow melted and water levels rose, the logs rolled into the river and the ride began. [6]

To keep the logs free to drag across the river, men called "log drives" or "river pigs" were needed to steer the logs. Drivers are typically divided into two groups. The more experienced and agile men consisted of the "jam" team or the "beat" team. They tracked where the logs could get stuck, and when a jam started, they tried to get to it quickly and dislodge key logs before many logs were stacked. Otherwise, the river would continue to pile up on more logs and form a partial dam that could raise the water level. [7] Millions of wood-foot lumber can be backed up for miles above the river, and while some timber is lost if pushed far enough into shallow areas, it will take weeks to break. [8] When the Jam team saw that a jam had begun, they rushed to him and tried to break him using peaveys and possibly dynamite. This job required some understanding of physics, strong muscles, and extreme agility. The jamming crew was an extremely dangerous occupation, with drivers standing on moving logs and running from one to the other. Many drivers died from falling on logs and being crushed. [7]