He gives it here in the same words as he communicated it to a friend at the time of its occurrence.
A few days since I went to the Boston Street school; the children were in the gallery, and the moment I entered, they rose to receive me.
When the school was over, the children came around me, as they usually do, saying, When will you come again?
and so on.

I told them I could not tell, but that I would come as soon as I could.

This answer would not satisfy them, and I talked to them until near six o'clock in the evening.

One little girl, about four years old, kept looking stedfastly at me the whole time, not letting a single word or gesture escape her notice.

At last I finished my observations, and desired the children to go.