Only to his intimates did he ever reveal the pain which sometimes gnawed at his heart, and then only occasionally and under great stress.

It was this self-control, united to a lofty purpose and a natural repugnance to wearing his heart on his sleeve, which enabled him to accomplish what he did.

Endowed also with a saving sense of humor, he made light of his trials to others and was a welcome guest in every social gathering.
The want of a place which he could really call home was an ever-present grief.

It is the dominant note in almost all the letters to his brothers and his children, and it is rather quaintly expressed in a letter, of November 14, 1838, to his daughter:-- "Tell Uncle Sidney to take good care of you, and to have a little snug room in the upper corner of his new building, where a bed can be placed, a chair, and a table, and let me have it as my own, that there may be one little particular spot which I can call _home_.

I will there make three wooden stools, one for you, one for Charles, and one for Finley, and invite you to your father's house." In spite of the enthusiasm which the exhibition of his invention aroused among the learned men and others in Paris, he met with obstructions of the most vexatious kind at every turn, in his effort to bring it into practical use.