Physicians who gave us Electricity | the story of William Gibert
We study 'Electricity' as a part of physics and also of engineering. So, it will be interesting to learn that some of the most significant discoveries relating to electricity were made by two medical men with no formal training in physics or engineering.
Thales had discovered that amber, when rubbed with silk, attracted light objects like small splinters of wood, bits of paper, etc. Sir Gilbert experimented with several materials and found that in addition to amber, materials like sulfur, glass, and sealing wax also attracted light objects. He published his book De Magenta in the year 1600 giving a detailed account of his experiments and findings. He named the mysterious attraction, electricity a word derived from 'Electra' the Greek word for amber.
The next important stage in the story of electricity is the discovery that it could be prepared by chemical action. To this, we are indebted to another physician Lungi Galvani and his famous experiment with frog legs. Professor Galvani taught anatomy at the University of Bologna, Italy. One day he was explaining to his students the complex network of nerves and muscles in frog legs on the table there was a plate with a pair of frog legs in it. Professor Galvani could not believe his eyes. So, he touched the legs again with the scalpel, and the legs jumped again.
A few days later, Galvani noticed another strange behavior of the frogs' legs He had hung out a pair of legs with copper clips from the iron railings of his balcony. In the gentle breeze, they swung back and forth. Whenever they touched the railings, they twitched. Galvani was mystified. He continued his experiments for eleven years. He concluded that it was electricity that caused twitching of the legs. He called it "Animal Electricity."
Galvani published an article describing in detail his experiments and observations. Soon the idea of Animal Electricity caught on. One of the scientists who got interested in it was Alessandro Volta, Professor of Physics at the University of Pavia. He was convinced that it was electricity which caused the twitching of frog legs. But, he doubted the existence of Animal Electricity. Finally, he got the clue from one of the observations recorded by Galvani. The legs twitched only when there were two metals. The scalpel and the plate, or the clip and the railings, had to be of two different metals.
From his experiment, Volta found that electricity was produced by the chemical action which took place when two different metals were in contact with a salt solution. This led to the invention of the storage battery.
In the case of Galvani's experiments, the salt solution was present in the frog legs. Though in the theory Animal Electricity was disproved, the scientific community gave due recognition to the Physician's experiments. Galvani's name has been immortalized by naming the instrument to measure the electric current "Galvanometer".
The word electricity was first coined by Sir William Gibert, who served as Chief Physician to Queen Elizabeth I. He was a reputed physician, but his interest was not confined to medicine alone. He had an inquisitive mind and took a keen interest in the developments in other branches of science also. He was fascinated by the stories of Thales, the Greek philosopher, and his experiments with amber.
Thales had discovered that amber, when rubbed with silk, attracted light objects like small splinters of wood, bits of paper, etc. Sir Gilbert experimented with several materials and found that in addition to amber, materials like sulfur, glass, and sealing wax also attracted light objects. He published his book De Magenta in the year 1600 giving a detailed account of his experiments and findings. He named the mysterious attraction, electricity a word derived from 'Electra' the Greek word for amber.
The next important stage in the story of electricity is the discovery that it could be prepared by chemical action. To this, we are indebted to another physician Lungi Galvani and his famous experiment with frog legs. Professor Galvani taught anatomy at the University of Bologna, Italy. One day he was explaining to his students the complex network of nerves and muscles in frog legs on the table there was a plate with a pair of frog legs in it. Professor Galvani could not believe his eyes. So, he touched the legs again with the scalpel, and the legs jumped again.
A few days later, Galvani noticed another strange behavior of the frogs' legs He had hung out a pair of legs with copper clips from the iron railings of his balcony. In the gentle breeze, they swung back and forth. Whenever they touched the railings, they twitched. Galvani was mystified. He continued his experiments for eleven years. He concluded that it was electricity that caused twitching of the legs. He called it "Animal Electricity."
Galvani published an article describing in detail his experiments and observations. Soon the idea of Animal Electricity caught on. One of the scientists who got interested in it was Alessandro Volta, Professor of Physics at the University of Pavia. He was convinced that it was electricity which caused the twitching of frog legs. But, he doubted the existence of Animal Electricity. Finally, he got the clue from one of the observations recorded by Galvani. The legs twitched only when there were two metals. The scalpel and the plate, or the clip and the railings, had to be of two different metals.
From his experiment, Volta found that electricity was produced by the chemical action which took place when two different metals were in contact with a salt solution. This led to the invention of the storage battery.
In the case of Galvani's experiments, the salt solution was present in the frog legs. Though in the theory Animal Electricity was disproved, the scientific community gave due recognition to the Physician's experiments. Galvani's name has been immortalized by naming the instrument to measure the electric current "Galvanometer".
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