From boyhood Franklin had been interested in natural phenomena.
His "Journal of a Voyage from London to Philadelphia", written at
sea as he returned from his first stay in London, shows unusual
powers of exact observation for a youth of twenty. Many of the
questions he propounded to the Junto had a scientific bearing. He
made an original and important invention in 1749, the
"Pennsylvania fireplace," which, under the name of the Franklin
stove, is in common use to this day, and which brought to the
ill-made houses of the time increased comfort and a great saving
of fuel. But it brought Franklin no pecuniary reward, for he
never deigned to patent any of his inventions.

His active, inquiring mind played upon hundreds of questions in a
dozen different branches of science. He studied smoky chimneys;
he invented bifocal spectacles; he studied the effect of oil upon
ruffled water; he identified the "dry bellyache" as lead
poisoning; he preached ventilation in the days when windows were
closed tight at night, and upon the sick at all times; he
investigated fertilizers in agriculture. Many of his suggestions
have since borne fruit, and his observations show that he foresaw
some of the great developments of the nineteenth century.

His fame in science rests chiefly upon his discoveries in
electricity. On a visit to Boston in 1746 he saw some electrical
experiments and at once became deeply interested. Peter Collinson
of London, a Fellow of the Royal Society, who had made several
gifts to the Philadelphia Library, sent over some of the crude
electrical apparatus of the day, which Franklin used, as well as
some contrivances he had purchased in Boston. He says in a letter
to Collinson: "For my own part, I never was before engaged in any