Page:Popular Science Monthly Volume 6.djvu/67

Rh duration of the pressure. For the left foot there is a grayish rectangle shaded with oblique lines. These alternations of gray and white express by their succession that in walking the pressure of one foot succeeds the other, without allowing any interval between the two.

Line 2 is the notation which corresponds with the ascent of a stair-case. It is seen that the strokes lap, or encroach on each other, and that, consequently, the body during an instant rests on both feet at once.

Line 3 corresponds with the rhythm of running. After a shorter pressure of the right foot than in the walking-pace, an interval is seen which corresponds with the suspension of the body; then a short pressure of the left foot followed by a fresh suspension, and so on continually.

Line 4 answers to a more rapid rate of running. It shows a shorter duration of the pressures, a longer time of the suspension of the body, and a more rapid succession of the various movements.

This method of representing the different modes of progression by the notation of their rhythms, though hardly necessary to make clear the simple paces of man, will greatly aid us in understanding the more complicated paces of the horse, which will be the subject of another article.



T the age of fifteen Mary was a remarkably fine and healthy girl: she seemed to be safely over the critical period, and, till after that time, had never suffered as many girls do at the commencement of their womanhood. Her thinking powers were quick and vigorous, and she was the pride of her teachers and joy of her parents. Unlimited mental progress was laid out for her, and it seemed that there were to be no bounds to her acquirements.

She had then finished a good common-school education, at the best high-school, and had entered an institute for young ladies (a boarding-school) of the highest character. The curriculum of study