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By age 42, Franklin was wealthy enough to retire from publishing and devote most of his time to his scientific pursuits, keeoing in touch with the leading scientists in Britain and the Continent.  Franklin combined commonsense empiricism, always paying very close attention to details and carefully recording his measurements. At the same time he was insatiably speculative, theoretical, and conjectural.  

By age 42, Franklin was wealthy enough to retire from publishing and devote most of his time to his scientific pursuits, keeoing in touch with the leading scientists in Britain and the Continent.  Franklin combined commonsense empiricism, always paying very close attention to details and carefully recording his measurements. At the same time he was insatiably speculative, theoretical, and conjectural.  

 

In 1742 he invented a device imnserted into a fireplace that gave more warmth at a lower fuel cost. His idea, worked out with his friend Robert Grace, consisted of a low stove, equipped with loosely fitting iron plates through which air circulated and was warmed before it entered the room. This "New Pennsylvania Fireplace" avoided drafts, gave more  even temperatures throughout the room, and checked loss of heat through the chimney.  It was an insert in an already existing hearth, and did not resemble what are now called "Franklin stoves".  

In 1744, he designed the "Pennsylvania Fireplace" (commonly known as the [[Franklin Stove]]<ref> See  [http://fi.edu/franklin/inventor/images/franklinstove.jpg illustration</ref>, a wood burning stove that fit inside a fireplace and maximized useful heat while producing less smoke.  The stove was not as practical as he had hoped, but it laid the groundwork for more efficient wood burning stoves.

Franklin's numerous other inventions include bifocal glasses<ref> see  [http://www.antiquespectacles.com/topics/franklin/franklin.htm illustration]</ref>, the glass armonica, the flexible catheter, the odometer, and swimming fins.  

Franklin's numerous other inventions include bifocal glasses<ref> see  [http://www.antiquespectacles.com/topics/franklin/franklin.htm illustration]</ref>, the glass armonica, the flexible catheter, the odometer, and swimming fins.  

On his many ocean trips he carefully monitored temperatures and currents, thereby discovering the [[Gulf Stream]] in the Atlantic Ocean.

The first contributions to scientific meteorology in America were Franklin's famous experiments regarding lightning, atmospheric electricity, cyclone theory, and ocean circulation, during the years from 1748 to 1775. Franklin designed the experiment that proved that electric sparks created artificially in the laboratory  were similar to deadly and destructive lightning bolts, except in magnitude. He proved that there were electric charges in the atmosphere both in cloudy (or thunder) weather and in fine weather. Franklin showed that storms may move  progressively "into the wind," by observing that a cyclonic storm with a northeast wind hit Philadelphia a day or so before it hit Boston, which lies to the northeast of Philadelphia. Finally, while crossing the Atlantic between 1746 and 1775, and after discussions with his cousin a ship captain, he reported there is a warm current off the New England coast setting to the northeast--the [[Gulf Stream]]--and was able to chart its boundaries fairly accurately.

==Physicist: Discovering electricity==

==Physicist: Discovering electricity==