For instance, suppose we are to draw a flower-pot and plant. If we have the picture before us, we can readily see where all the lines are placed upon the paper, but in viewing a real plant and pot we are apt to become confused in trying to discover the directions and proportions of the lines.
Therefore we must learn to see things as they appear, not as they really are. This may seem strange to you, because one is apt to think that a thing must appear as it is; but let us look into the matter.
We will take a square box (Fig. 140). Now, we know that all the sides are the same size, that the top is as large as the side, and that one side is as large as another; but if you try to draw it so, you will find it impossible, because, although you know that the top and sides are the same size as the front, they do not look so, and you draw things as they look, not as they really are.
What would our cube look like if we tried to make the sides K and H just like the side I? Why, like Fig. 141. Don’t you see that would be no box at all?
Take another example. We all know that a man’s leg is longer than his arm, but it doesn’t always appear so. Measure the arms and legs of Fig. 142, and you will see by actual measurement the arms are longer than the legs, and yet it looks right, because the legs are projected toward you; in other words, the legs are fore-shortened.
The great secret of drawing from nature is to train the eye to see a real object just like a picture.
Now let us return to our flower-pot again. We will suppose we are drawing from a real flower-pot and plant. We determine how large we will make our sketch, and begin operations by drawing a vertical line (a straight upright line). Along this line we will mark out the proportions of the plant and pot, as in Fig. 143.