physical principles, whether applied to mechanics, or astronomy, may be made to subserve the same purpose as means of education.
The applicate and the mixed sciencesmechanics, pneumatics, hydraulics, hydrostatics, optics, acoustics, abound with instances, available for the same purpose; and as often as some familiar incident of domestic life can be connected, by means of a word or two of scientific explanation, with philosophical principles, the mind of the learner is carried through a similar process, advancing from what obtrudes itself on the senses, to that which calls the higher faculties into play. Such a circumstance has occurred at a tea-table, as that of the heater of the urn rushing up, impatient of its obseurity, and carrying the lid with it, like a broad brimmed hat, to the ceiling. What could we wish for better than such an incident (if no heads were broken by the descending mass) as an illustration of the principle of the steam-engine? A fit question, when tranquillity was restored, after such an accident, would have beenWhat mechanical contrivance does this explosion put us in mind of? and the wordthe steam-engine, uttered in a moment, and of course, by one of the elder children of the family, would stimulate the curiosity of those next in degree below them.
This kind of incidental exercise, no well-informed teacher can need to have exemplified at length; and the occasions are innumerable in which it may be put in practice. After having, as was recommended in a preceding chapter, gone over the entire ground of the physical sciences in search of such facts as are proper for enriching the ideal faculty; I now suppose that the teacher returns upon his path, and gleans thence another sort of material, that is to say, those allied or analogous facts, such as have been mentioned, which penetrate the mind a little deeper, and arouse it more to action. Conceptuality is passive, or
