A lecture about an experiment

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In today's lecture we're going to be talking about experiments, and I thought it might be interesting for you all to learn about the world's oldest continuously running laboratory experiment that is still going today. In fact, it holds the Guinness World Record for being the longest-running experiment. This experiment began in 1927 and has been going ever since.

It's called the 'pitch drop' experiment and it was created by Professor Thomas Parnell at the University of Queensland, Australia. Parnell was the university's first physics professor, and he wanted to show in this experiment that everyday materials, such as pitch, can have quite surprising properties.

You see, when pitch is at room temperature, it feels solid. You can easily break it with a hammer. However, it isn't in fact solid. At room temperature, pitch is many billions of times more viscous than water, but it's actually fluid.

In 1927, Professor Parnell took a sample of pitch. He heated it and poured it into a glass funnel. He allowed the pitch to cool and settle – for three years. He then turned the funnel upside down and cut the top off it.

Since then, the pitch has slowly dropped out of the funnel. How slowly? Well, the first drop took eight years to fall. It took another forty years for another five drops to fall. Today it's been almost 90 years since the experiment started. Only nine drops have fallen from the funnel. The last drop fell in April 2014 and the next one is expected to fall in the 2020s.

The experiment has a tragic story associated with it. Professor Parnell died without seeing a pitch drop. His replacement, Professor John Mainstone, became responsible for the pitch drop experiment from 1961. He held the job for 52 years, and missed seeing the drop fall three times – by a day in 1977, by just five minutes in 1988 and finally in 2000, when the webcam that was recording the experiment suffered a power outage for 20 minutes, during which time the pitch dropped.

The pitch drop experiment is something we can all participate in now. There's a live web stream that allows anyone to watch the glass funnel and wait for the fateful moment. A similar experiment to the Queensland pitch drop was set up in Dublin, and the video of the moment the pitch actually dropped went viral on the internet. It's interesting to see how a very slow event can spread news so quickly.

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Discussion

Do you know of any other famous experiments? What are they?

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Language level

B2 Upper intermediate

Topics

science and technology

Actually I can't remember any famous experiments, expect this pitch drop, I'll do some research to know more about it

Version reviewed and reformulated by ChatGTP

Famous Experiments and Theories Throughout History

Throughout human history, countless experiments have been conducted across various fields, including philosophy, mathematics, architecture, medicine, agriculture, and psychology.

I remember learning about famous scientists, philosophers, and discoverers in high school, from antiquity through the Middle Ages to modern times. However, the ones I will never forget are :

Charles Darwin – His theory of evolution states that all species of organisms arise and develop through natural selection, where inherited variations that enhance an individual’s ability to survive and reproduce become more common over time. According to this theory, chimpanzees and humans share a common ancestor, evolving over millions of years into separate species.
Isaac Newton – He established the laws of motion and gravity, stating that an object in motion stays in motion unless acted upon by an external force, that force equals mass times acceleration, and that every action has an equal and opposite reaction. His famous "apple incident" is often cited as the inspiration for his theory of gravity.
Marie Curie – She is remembered for discovering radium and polonium and for her groundbreaking research in radioactivity, which contributed significantly to cancer treatment.
Ivan Pavlov – His famous experiment with dogs demonstrated classical conditioning. By ringing a bell before feeding them, he conditioned the dogs to salivate at the sound of the bell alone, even when no food was present. This experiment showed that behavior could be trained through repeated association, a principle widely used in behavioral psychology and education today.
Cesare Lombroso – In 1876, the Italian criminologist proposed a biological theory of criminality, suggesting that criminals were "born" rather than "made" and could be identified by their physical characteristics, such as facial asymmetry or large jaws. His controversial theory influenced early criminology, though modern research has largely discredited it in favor of social and environmental explanations for criminal behavior.

Darwin’s and Lombroso’s theories remain highly controversial. Many scientists and religious scholars reject them—some on the basis of scientific studies and research, others due to religious beliefs.

I haven't heard of this experiment before but it seems very interesting to me.

The experiment was very interesting. Now, I don't remember from another experiment, but I learned a new thing.

Thank you.

I pitifully do not know about any other famous experiment. I do know about regular experiments that I learned in the school or the most famous that you always hear, but no different from them.

At university, I learnt about several interesting experiments made in physics, but the "pitch drop" is really very curious to know.
The first experiment I did was when I was at the primary school. It was a botanic experiment. I put some beans on the bottom of a glass for bear, I make them wet and then I covered them with some cotton. After some days, I saw the roots coming out of the beans: a new plant was growing! That made me very happy.

My favourite is Isaac newton's law of motion and forces experiments that made him one of the greats of science

Yes, I can certainly tell you about some famous experiments from various fields of science and psychology. Here are a few notable ones:
-Stanford Prison Experiment (1971)
-Little Albert Experiment (1920)
-Double-Slit Experiment (1801)
-Pavlov's Dogs (1890s)
-Hawthorne Studies (1920s-1930s)
-Skinner's Box (Operant Conditioning Chamber)
-Asch Conformity Experiments (1950s)
These experiments have had a lasting impact on their respective fields and have often raised ethical and philosophical questions about human behavior, perception, and ethics in research.

Honestly, I don't remember any famous experiment like the pitch experiment. However, I find it intriguing and haven't heard of it before. After completing my current task, I plan to look for the live stream out of curiosity.

I remember an experiment carried out by Galileo during the Renaissance. He dropped two balls of the same size but different weights on an inclined floor and saw that they both ran at the same speed past each other. He then concluded that in free fall, the acceleration due to gravity is not affected by the weight of objects.