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Knowledge is power but wisdom is the key to success

Born in 1879 was Agnes Arber FRS. Arber was a British plant morphologist and anatomist, historian of botany and philosopher of biology. She was elected as a fellow of the Royal Society in 1946, the first woman botanist to be elected.

Modernity stands on the shoulders of . Their historical foundations support and inspire our today. In 19th century, in Germany, there was such a historical man, who had the ability to integrate book knowledge with fundamental bench . That man is our "scientist of the day" today.

It's the birthday of , the father of frequency --

(Scientist of the Day - 22 February)

In 1877, Hertz enrolled at the polytechnic in , where he encouraged by his teachers, to study the original works of famous physicists such as Isaac , Gottfried , Joseph , and Pierre-Simon . But he was dissatisfied with the level of physics education in Munich, so he moved to Berlin where he studied under Hermann von & .

In 1883, he began his studies of ’s electromagnetic theory. Between 1885 and 1889, while he was .....

You can read the full article about his works for electromagnetic waves & effect, here, https://www.instagram.com/cosmological_astrophysics

"As a child of economists, I knew that economics was one field I must avoid. My father was a famously charismatic teacher, who adored and was much adored by his many students. He would often talk about just how brilliant some of them were, and it was clear to me that I had nothing to gain and much to lose by inviting comparisons with them. In my deeply anti-intellectual high school, it was made very clear that we should all aspire to study engineering or medicine because they led to good jobs (the lure of jobs in finance came many years later). They made an occasional exception, in the case of an unusually brilliant student, for studying phys­ics. I had no desire to be an engineer or a doctor and prepping for physics required consorting with our physics teacher, a man who seem to take genuine pleasure in inflicting pain. What else could I do? I loved literature and history, philosophy and math; my parents were against the first three. Their stated grounds were that I could always go from math to those at a later stage but not the reverse, though my guess now is that they were not sure that I was good enough to make a living in the humanities, given the shape of the labor market. In any case their argument for math appealed to my instinct for trying to postpone all hard choices. Math it was going to be."

Read Abhijit Banerjee's newly published biography on nobelprize.org where he tells us about his life journey to becoming a prize awarded economist: https://www.nobelprize.org/prizes/economic-sciences/2019/banerjee/biographical/

“The results which I have attained will be considered absolutely impossible by any competent electrical engineer. Ever since Faraday, we have had certain laws of induction which were considered absolutely inescapable. One of these is that when lines of force are linked with a circuit an electrical current is produced in the same, it was not possible to take those lines out of the circuit without inducing an equivalent flow of current in the opposite direction.”

“Thousands of inventors and scientists have bucked against this difficulty in vain, and those who were the most competent never even tried to attain such a result, being convinced that experiments in that direction were useless. Now, incredible as it seems, I have found a solution of this old problem and not only am I able to produce a current in one direction in a current by induction, without a commutator, but also can make this current almost as steady and continuous as that from a battery. It has been the desire of my life to achieve this.”

–Nikola Tesla

“Tesla, at 79, Discovers New Message Wave.” New York Herald Tribune, July 11, 1935.

4 Main Eras In Electrical Development:

1. 1780-1831 Luigi Galvani and Alessandro Volta: The discovery and exploitation of the Galvanic Current.

2. 1831 Michael Faraday: Period of induction.

3. 1868 Werner von Siemens , Henry Wilde, Antonio Pacinotti, and Zénobe Gramme: Direct current machines.

4. 1888 Nikola Tesla: Three-phase alternating current machine.

This delightful orrery from 1761 shows the planet Venus, the Earth and the Sun. Turning the handle on the left would cause Venus to rotate around the Sun. In 1769, the Royal Society sent an expedition to view the transit of Venus from Tahiti. https://pictures.royalsociety.org/image-rs-3383