Skip to content
Vatican Observatory
  • About
    • Overview
    • Team
    • FAQ
  • Telescopes
    • Overview
    • Telescope Images
  • Tours
    • Castel Gandolfo
    • U.S.
  • Latest
    • Overview
    • Resources
    • Press
    • Audio
    • Video
    • Research
    • Authors
      • FAQs
    • Newsletter
    • Tucson Meteor Cameras
  • Podcast
  • Education
    • Overview
    • Resource Center
    • Image Gallery
    • Summer School
    • Books
    • Software
    • Additional Resources
    • ACME
  • Shop
  • Calendar
    • View our Event Calendar
  • Donate
    • Donate Now
    • Smart Ways to Give
    • Sacred Space Astronomy
      • View Content
    • Bequests / Trusts
    • The Foundation
      • Newsletters
      • Annual Reports
  • Press
    • VO in the News
    • Press Kit
  • Specola Vaticana
  • Contact
    • Contact
  • About
    • Overview
    • Team
    • FAQ
  • Telescopes
    • Overview
    • Telescope Images
  • Tours
    • Castel Gandolfo
    • U.S.
  • Latest
    • Overview
    • Resources
    • Press
    • Audio
    • Video
    • Research
    • Authors
      • FAQs
    • Newsletter
    • Tucson Meteor Cameras
  • Podcast
  • Education
    • Overview
    • Resource Center
    • Image Gallery
    • Summer School
    • Books
    • Software
    • Additional Resources
    • ACME
  • Shop
  • Calendar
    • View our Event Calendar
  • Donate
    • Donate Now
    • Smart Ways to Give
    • Sacred Space Astronomy
      • View Content
    • Bequests / Trusts
    • The Foundation
      • Newsletters
      • Annual Reports
  • Press
    • VO in the News
    • Press Kit
  • Specola Vaticana
  • Contact
    • Contact

From the Cabinet of Physics: Conveying Heat across Space

By Bill Higgins  |  16 Jul 2016

Share:
  • Share on Facebook
  • Share on Twitter
  • Share on LinkedIn
  • Share via Email

This entry is part 8 of 23 in the series From the Cabinet of Physics

Today’s demonstration from the Cabinet of Physics appears at first to be about optics but, in a surprising twist (SPOILER ALERT), turns out to be about heat.

A curved mirror, a paraboloid, reflects the light of a candle flame to another curved mirror some distance away. The candle sits at the focal point of the first mirror. The second mirror brings the light to its own focal point; hold a white card at this precise spot, and you’ll see an image of the candle flame.

Now the candle is replaced by a collection of burning lumps of charcoal. Across the room, a piece of tinder is placed at the focus of the second mirror. To the eye, the coals seem much dimmer than the candle flame. The mirrors are gathering not only the visible light, but also the more copious invisible infrared light emitted by the coals.

The unseen radiant heat is energetic enough to ignite the tinder. Soon it too is glowing red, and smoke is rising. It’s a nice example of the close kinship between light and radiant heat.

Perhaps the novelist H. G. Wells had a demonstration like this in mind in 1897 when, in War of the Worlds, he imagined Martian invaders incinerating the English landscape with “heat rays.”

This apparatus reminds me of a story. The physicist Theodore Taylor was responsible for a most peculiar application of focused heat radiation. At an observation post in a Nevada desert on 5 June 1952, Taylor was waiting for the test of a nuclear bomb he had designed.  He took a small parabolic mirror and attached a rig, made out of wire, that could hold the tip of a cigarette at the mirror’s focal point.   He aimed the mirror carefully at the distant weapon. At the end of a countdown, intense visible and infrared light engulfed the test site. Miles away, Taylor withdrew his Pall Mall from the mirror and took a puff. He had invented the first nuclear-powered cigarette lighter.

The Foundation for Science and Technics, or Fondazione Scienza e Tecnica, of Florence, Italy, has made available many videos exploring the Cabinet of Physics, a large collection of antique scientific demonstration instruments.  The Foundation’s homepage may be found here, and its Youtube channel, florencefst, here.

Share:
  • Share on Facebook
  • Share on Twitter
  • Share on LinkedIn
  • Share via Email

Sacred Space Astronomy

The Vatican Observatory’s official digital community and online magazine.

Become a Member

Recent Posts

Corkscrew Prom

By Deirdre Kelleghan  |  21 May 2025  |  Sacred Space Astronomy

From the Vatican Observatory Faith and Science pages (Younger Readers) — Gregor Mendel: The Friar Who Grew Peas

By Faith and Science  |  21 May 2025  |  Sacred Space Astronomy

Visit of Br. Guy Consolmagno S.J.

Pluscarden Abbey  |  19 May 2025  |  Press

The Skull of St. Thomas Aquinas, Realities, and Science

By Mr. Christopher Graney  |  17 May 2025  |  Sacred Space Astronomy

Archives

      • May
      • April
      • March
      • February
      • January
      • December
      • November
      • October
      • September
      • August
      • July
      • June
      • May
      • April
      • March
      • February
      • January
      • December
      • November
      • October
      • September
      • August
      • July
      • June
      • May
      • April
      • March
      • February
      • January
      • December
      • November
      • October
      • September
      • August
      • July
      • June
      • May
      • April
      • March
      • February
      • January
      • December
      • November
      • October
      • September
      • August
      • July
      • June
      • May
      • April
      • March
      • February
      • January
      • December
      • November
      • October
      • September
      • August
      • July
      • June
      • May
      • April
      • March
      • February
      • January
      • December
      • November
      • October
      • September
      • August
      • July
      • June
      • May
      • April
      • March
      • February
      • January
      • December
      • November
      • October
      • September
      • August
      • July
      • June
      • May
      • April
      • March
      • February
      • January
      • December
      • November
      • October
      • September
      • August
      • July
      • June
      • May
      • April
      • March
      • February
      • January
      • December
      • November
      • October
      • September
      • August
      • July
      • June
      • May
      • April
      • March
      • February
      • January
      • December
      • November
      • October
      • September
      • August
      • July
      • June
      • May
      • April
      • March
      • February
      • January
      • December
      • November
      • August
      • June
      • March
      • January
      • November
      • October
      • December
      • November
      • April
      • May
      • January
      • December
      • September
      • May
      • March
      • December
      • November
      • February

More Posts in this Series:
"From the Cabinet of Physics"

Nature’s “Where I Work” Photography Exhibition at King’s Cross Shows Br. Guy Consolmagno

By Robert Trembley  |  23 Apr 2024  |  Sacred Space Astronomy

Press Release: New cosmological research of the Vatican Observatory

By Robert Trembley  |  26 Mar 2024  |  Sacred Space Astronomy

“Faith in Science: Catholic and Jewish Perspectives on Creation and the Cosmos.”

YouTube  |  6 Nov 2023  |  Press

Seeking God in science is part of Jesuit’s vocation

YouTube  |  25 May 2022  |  Press

Newsletter

Upcoming astronomical events, scientific breakthroughs, philosophical reflections… just a few reasons to subscribe to our newsletter!

Vatican Observatory
  • About
  • Telescopes
  • Tours
  • Latest
  • Podcast
  • Education
  • Shop
  • Calendar
  • Donate
  • Press
  • Specola Vaticana
  • Contact
Privacy Policy  |   Cookie Policy  |   Disclosure Statement  |   This website is supported by the Vatican Observatory Foundation

Podcast:

  • Apple Podcasts Listen onApple Podcasts
  • Spotify Listen onSpotify
  • Google Podcasts Listen onGoogle Podcasts
  • Stitcher Listen onStitcher
  • Amazon Alexa Listen onAmazon Alexa
  • TuneIn Listen onTuneIn
Made by Longbeard