In a letter to Mary Stevenson (written, it is thought, in November 1760, or sometime in 1761), Mr. Franklin said:
My Experiment was this. I took a number of little Square Pieces of Broad Cloth from a Taylor’s Pattern Card, of various Colours. There were Black, deep Blue, lighter Blue, Green, Purple, Red, Yellow, White, and other Colours or Shades of Colours. I laid them all out upon the Snow in a bright Sunshiny Morning. In a few Hours (I cannot now be exact as to the Time) the Black being warm’d most by the Sun was sunk so low as to be below the Stroke of the Sun’s Rays; the dark Blue almost as low, the lighter Blue not quite so much as the dark, the other Colours less as they were lighter; and the quite White remain’d on the Surface of the Snow, not having entred it at all. What signifies Philosophy that does not apply to some Use? May we not learn from hence, that black Cloaths are not so fit to wear in a hot Sunny Climate or Season as white ones; because in such Cloaths the Body is more heated by the Sun when we walk abroad and are at the same time heated by the Exercise, which double Heat is apt to bring on putrid dangerous Fevers? That Soldiers and Seamen who must march and labour in the Sun, should in the East or West Indies have an Uniform of white? That Summer Hats for Men or Women, should be white, as repelling that Heat which gives the Headachs to many, and to some the fatal Stroke that the French call the Coup de Soleil? That the Ladies Summer Hats, however should be lined with Black, as not reverberating on their Faces those Rays which are reflected upwards from the Earth or Water?That’s a good brief example of Mr. Franklin’s thinking. He uses methods of induction, esp. concomitant variation, to determine a causal relationship — which he then integrates into the rest of his knowledge, applying what he learned to health, clothing and comfort. But such considerations, such a broader context, also motivated his research in the first place. And that kind of thinking and style seems to be reflected in what An American Guesser would write about a rattlesnake and the American colonies. And that is an example of how “hands on” should come into play in learning: as a part of a process of reasoning. With emphasis on “reasoning.” I guess we could say “Reasoning: It’s fundamental.” See The Papers of Benjamin Franklin for more: the letters of Silence Dogwood and Mr. Franklin’s Autobiography included.