Note the relation of earth to sky, and of trees to hills, streams, or other objects to be included in the sketch. As a help to find the true direction compare the surface planes and edges with that which you know is vertical. Study the light and shade, choose the simple broad tones which will best express distance, middle ground and near details. Work simply and easily, not straining after certain preconceived effects. It is this particular truth or fact which now appeals to you, which you are to express, and do not hesitate to express it freely and boldly. Sketch everything, anything, no matter how complicated it may seem to be, and sketch often. The child does that, and learns to draw by drawing.
31
[Fig. 25] shows the edge of a desert in Wyoming Territory, where the only vegetation is sage brush. The rains have worn a little gully in the general sandy level. Notice the steep slant of the sandy sides. [Fig. 26] is a sketch of a hole in the sandy soil of a farm, on the banks of the Au Sable River, New York. It was first worn by the rains as a little gully on the upper edge of the bank, and with every rain-storm more sand was washed out and carried down into the river. A part of this is deposited lower down the river, below the bank on the right, in the sketch [Fig. 30].
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Use horizontal lines for the sandy level, and curved lines to indicate the slow current in the water. [Fig. 27] also shows the result of rain and wind erosion of the bank behind the stump of the tree. [Fig. 28] represents a section of Yellowstone cañon, and [Fig. 29] is a sketch from Monument Park, Colorado. In both the latter are seen examples of rain and wind erosion, more particularly in [Fig. 29]. Notice the hard layers of rock that cap and protect the softer sandstone beneath, and the hard pinnacles that jut out from among the sliding sands in [Fig. 28].
33
The effects of river erosion, together with the weathering of rocks are seen in [Fig. 31], which is a sketch of a section of Wilmington Pass, in the Adirondacks. The precipitous sides of rock, are shown with evergreens growing wherever they can find a foothold in the soil made by the disintegration of the rocks above. Boulders and trees have been brought down by the loosening of masses of rock, through the action of frost, heat, and melted snow, causing obstructions in the stream, over and between which the waters tumble and roll. [Fig. 32] is a view taken from the beach of Arch Rock, at Mackinac Island. It is a mass of calcareous rock, showing the result of lake erosion and weathering. The rock in [Fig. 33] shows signs of disintegration from the action of wind and rain.