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• Art Duval

Scaling lumber, cording firewood

How would they calculate a forest's worth in Pioneer times?

This tool. It is made by Lufkin Rule company in Michigan. People involved in appraising lumber for the lumber industry would use a rule like this with all the calculations necessary to evaluate the amount of board feet of lumber was available in the bush.

To read the scale you needed to follow the following 6 steps (from the website How to Read a Doyle Log Scale Rule (ehow.com):

Step 1 Place the Doyle Log Rule against the trunk of the tree 4 feet off the ground, and stand so that your eyes are at the height of the ruler and 25 inches away from it.

Step 2 Adjust the left-to-right orientation of the ruler so that the left end of the ruler aligns with the left edge of the trunk from your vantage point 25 inches from the ruler.

Step 3 Shift your line of sight to the right without moving your head, and note where the right side of the trunk passes behind the ruler from your vantage point. The edge will intersect with a diameter reading along the top of the ruler, which represents the approximate diameter of the tree. It is important to maintain the 25-inch distance and to keep your head stationary to maximize accuracy.

Step 4 Stand 66 feet from the tree and hold the ruler vertically with the "Number of 16 Foot Logs" scale facing you.

Step 5 Hold the ruler 25 inches from your eyes, and align the bottom of the ruler with the top of the stump of the tree. The stump ends where the tree first narrows from its roots to the size of the diameter for the trunk, approximately 1 foot above the ground.

Step 6 Read the right side of the log scale ruler at the highest point at which the trunk is approximately 6 to 10 inches in diameter. The numbered lines represent full logs, 16 feet long, while the dashes without numbers between the numerals represent 8-feet-long half logs.

Step 7 Consult the chart on the Doyle Log Scale Ruler and find the number in the grid that corresponds with the diameter found in Step 3 and the height found in Step 6.

So obviously not a simple process but one employed by people quite regularly throughout North America in the times of the Lumber trade.

The Doyle scale is the standard by which hardwood lumber is bought and sold. It estimates large or medium logs very close to the actual number but underestimates in smaller logs. Because it comes in below the price, this is the scale most log buyers want to use.

How is Doyle scale calculated?

The Doyle Rule (Table 1) is the most widely used rule, especially on private timber in the east and south. The formula is simple and easy to remember. This formula says to subtract four inches from the diameter for slabs and edgings, square the result, and adjust for log length.

Another way to measure wood is by the cord. This method is not for lumber but for wood used in heating.

A Bush cord is measured when the wood is cut, and still in the bush on the most part. Bush cords are stacked 4 feet high by 4 feet deep by 8 feet wide. The bush cord is usually not useable in a wood stove or fireplace and needs to be cut down to 16 inches, a standard measurement useable.

Face cord

A face cord is generally used when the wood is sold. Cut down to 16 inches, it is still 4 feet high by 8 feet long. It is split and cut and after a seasoning, period of time it takes to dry, is available to the end user to be burnt in a fireplace or woodstove.

Both in lumber and firewood it is preferable to have hardwood. In Canada, hardwood is mostly deciduous, oak, maple, and beech are examples of hardwoods.

Softwood is derived from conifers, and include pine and cedar. Although most uses hardwood is preferable, some species, like cedar is has uses, especially in wet weather worn areas of construction. Pine also has it's own uses, including the manufacturing of plywood.

Art Duval

Pipesmoke of the past