Birth of branches and the straightness of the grain in wood
Four modes of branch arrangement, and advice to the painter to study from nature
Notes on how branches arise on plants, with branch and trunk sketches down the right margin. Four modes are set out by which branches and leaves succeed one another up the stem: the sixth above the sixth below, two-thirds over two-thirds, one-third over one-third, and the tiered arrangement of the fir. A second note explains why timber is often not straight in its grain: when the following year's branches grow unequally and to one side, the trunk's vigor twists toward the higher branch and the veins run crooked, whereas even branching keeps the veins straight and parallel. The passage closes by urging the painter to draw everything from nature and not to despise study, as the money-seekers do.
On this page
Four modes of branch and leaf arrangement up the stem
Branches arise on the main stem as leaves arise on the year's branchlets, in four modes. Most universal is the sixth above born over the sixth below; then two-thirds over two-thirds; then one-third over one-third; and lastly the fir, which sets its branches in tiers.
Why the grain of timber runs crooked or straight
When the next year's branches grow unequally and off to the side of the earlier branch, the lower branch's vigor twists toward feeding the higher one, and the trunk's veins run crooked. Where branchings grow with equal strength, the veins of the trunk stay straight and equidistant at every height.
Advice to the painter: draw everything from nature
The note turns to the painter, warning that without these rules he cannot escape the censure of the knowing. He is urged to be eager to portray every natural thing from life and not to despise study, as the money-seekers do.
Marginal branch and trunk-grain sketches
The right margin holds several sketches: branching stems, a leafy plant, and a striped column-like drawing standing for the veins of a trunk. They illustrate how branch arrangement governs whether the grain of the wood runs straight.