Lightning

Joseph Henry was always interested in atmospheric electricity and his lifelong study with thunderstorms played an important role in his research about electromagnetism. Henry started his largest investment with lightning in July, 1841 in Princeton, when a very severe thunder storm hit Princeton. The list below shows the major writings and records during this period. Before 1841, Henry had also shown interest in electrical storm before this investment:

 

Following are the major writings and experiment records by Henry on his study of lightning from 1841 to 1846, during which period Henry was mainly engaged with the study of induction and discharge.

1. July 15th, 1841. Henry’s first extended account in his record of experiments of an observation on a thunderstorm.

2. July 16th, 1841 Another record of the observation on the same thunderstorm on July 14th.

3. November 5th 1841, American Philosophical Society, “On the Effects of a Thunder Storm”, recording the investigation of the storm on July 14th, mention in the two records above.

4. Sept. 2nd, 1841, a experiment short account about effects of lightning induction at a distance

5. June 10th, 1842, record of experiments about induction from thunderstorm. Needles were used for detection.

6. June 13th, 1842, record of experiments about induction from thunderstorm. Needles were used for detection.

7. July 22nd 1842, a record of Henry’s visit to a house struck by lightning.

8. June 20th, 1845, American Philosophical Society, On the Protection of Houses from Lightning

9. June 19th, 1846, American Philosophical Society, On the Relation of Telegraph lines to lightning.

Several of his early experiments on induction from lightning were mentioned. From the 4th section, P.7, first paragraph, it seemed that Henry was not clear about the difference between electromagnetic induction and radio transmission and reception.