From a book recently donated by T.W. Sills. A classroom
experiment explained in Richard Green Parker, A
School Compendium of Natural and Experimental Philosophy.
17th edition (New York, 1850). As one learns from the book's front matter,
it was used in the schools of Boston from 1838. In 1847, Parker (a principal
of a Boston grammar school) issued a revision to incorporate recently
purchased teaching apparatus "substituted for the cheap and defective
sets" formerly in use.
From a book recently donated by T.W. Sills. A lesson from Mary A. Swift,
First Lessons in Natural Philosophy for Children, Part Second (Hartford,
1853). Such books were widely used for home instruction in rural areas.