From The Royal Institution.

Our ability to make very precise measurements has impacted the process of science in innumerable positive ways, but is it possible to take it too far?

Watch all the lectures in this series here: https://youtube.com/playlist?list=PLbnrZHfNEDZw-UIpDJcH_g8d6Ii84pEDs&si=6_78ZnKHL-OglB4x
Watch our newest Christmas lectures here: https://www.youtube.com/playlist?list=PLbnrZHfNEDZyQJZLPMjwEoOLdkFBLU2m1

This was recorded on 6 Dec 1981.

—

From the 1981 programme notes:
In some instances, our ability to make very precise measurements has profoundly affected human thought, and even affected the character of life. The measurement of the shadows of sticks at Alexandria and Syene enabled Erathosthenes about 230 BC to estimate the circumference of the earth; and knowledge of this kind, combined with information from navigational instruments such as the compass, helped Columbus to keep direction on dark overcast nights, and thus led to the discovery of America. Tycho Brahe’s attempts to observe the distance of a nova showed that it was as far away as the other stars, and thus that the remote heavenly bodies were not immutable, and his precise measurement of the positions of Mars led to Kepler confirming and extending the ideas of Copernicus about the solar system, and thus to the realisation that we are not at the centre of the universe. Joule’s precise measurements of temperatures led him to discover the great principle of conservation of energy. The discovery by Lord Rayleigh that nitrogen prepared chemically was about one part in one thousand lighter than that filtered out from the air, led to the discovery of argon and hence of helium, on which much modern technology depends. And Aston’s measurement to one part in ten thousand of the relative masses of atomic nuclei led to the discovery of ways in which atomic energy could be released.

If there is time, we may pause to consider why sometimes the advance of science has depended on such very precise measurements, and at other times on very crude experiments such as those which led Rutherford to discover the atomic nucleus. And we shall see that, although appearing so very different in character, both kinds of experiments are part of the same process.

We shall also hope to look at two triumphs of modern technology which depend directly on our ability to measure and control mechanisms with precisions of better than one ten-thousandth of a centimetre.

—

About the 1981 CHRISTMAS LECTURES
The Christmas Lectures at the Royal Institution started in 1826, and there have now been more than one hundred and fifty in the series; and yet none has previously been on the theme of this year’s lectures, which is measurement. Perhaps this is because the measurement is so much part of human life that we tend to take it for granted; but if we are to understand how our modern world, with all its achievements and its dangers, has evolved, then we need to know what measurement is, the principles by which measurements can be made, and why their applications have been of so much importance in the advance of science and in the development of technology. And we also need not be carried away by the spectacular successes of measurements, such as awakening mankind to the huge store of energy in the atomic nucleus, or the microchip, or the control of space probes as far away as Saturn; for despite Plato’s proud claim that ‘man is the measure of all things’ there are many qualities in life that are very difficult, if not impossible, to measure such as love or courage, and we should therefore be cautious about extending measurement beyond its proper domain. But within that domain, measurement is one of the most challenging, fascinating and rewarding of human activities: this is what the lectures are intended to show.

Find out more about the CHRISTMAS LECTURES here: https://www.rigb.org/christmas-lectures

—

Join this channel to get access to perks:
https://www.youtube.com/channel/UCYeF244yNGuFefuFKqxIAXw/join

Subscribe for regular science videos: http://bit.ly/RiSubscRibe

The Ri is on Twitter: http://twitter.com/ri_science
and Facebook: http://www.facebook.com/royalinstitution
and TikTok: https://www.tiktok.com/@ri_science
Listen to the Ri podcast: https://podcasters.spotify.com/pod/show/ri-science-podcast
Donate to the RI and help us bring you more lectures: https://www.rigb.org/support-us/donate-ri
Our editorial policy: https://www.rigb.org/editing-ri-talks-and-moderating-comments
Subscribe for the latest science videos: http://bit.ly/RiNewsletter

Product links on this page may be affiliate links which means it won’t cost you any extra but we may earn a small commission if you decide to purchase through the link.