Singing takes much _out_ of the teacher, which will soon be felt in the chest, and cause pain and weakness there; and, if persevered in, premature _death_; and with women much sooner than men.

This is another reason why one of each sex should be employed in the work.

Singing is an exhilarating and exciting lesson; the children always like it: but even they are injured by the injudicious management of it, and by having too much of it each day; or the having two or even three exciting lessons at the same time.

For example: I have seen children singing, marching, and clapping hands at the same time; and they are prompted and led by the teachers to do so.

Here are three exciting lessons together, which ought to be separate: the result is, a waste of energy and strength, on the part of teacher and children, which is sometimes fatal to both.
The exciting lessons were intended to be judiciously blended with the drier, yet necessary, studies.