There are a few things which we still cannot count, such as the blades of grass, the ears of corn, drops of rain, snowflakes, and hailstones.

All of these things are still spoken of in the singular, though this is well known to be scientifically incorrect.

We say an expanse of grass, a field of corn, and so on, as if the grass and corn were all one plant instead of an innumerable quantity of plants.

Apparently when primitive man saw a number of animals or trees of the same species together, the effect on him must have been exactly the same as that of a field of grass or corn on us.

He could be conscious only of an indefinite sense of magnitude.