Page:Popular Science Monthly Volume 32.djvu/752

730 taken for each year. The sum of the differences of the second year (being less in both classes of students) was subtracted from the sum of the differences of the first year. The remainder was a gain in symmetry. This remainder, divided by the sum of the differences of the first year, gave the percentage of "gain in symmetry."

It must not be forgotten that the conditions of American life have changed so greatly in the last century that, in order to view education aright, it is necessary to take counsel of new considerations. To be sure, the material to be worked on seems to be the same. The youthful mind and character are unchanged. Yet there are influences at work in these modern times which are destined to sap the physical strength of our young men, and thus impair the vigor of their minds and emasculate their characters, unless these influences be clearly recognized and continually counteracted. We will mention two of these influences:

1. —According to the last census report, of every one hundred inhabitants in the United States, there were dwelling in towns of eight thousand inhabitants and above—

But these figures do not tell the whole story. Towns have grown into cities, and cities have added to their population enormously in the thirty years from 1850 to 1880, as will be seen from the following figures, showing the number of cities of various grades: