Archives for August 2014

A selection of brilliantly quotable quotes from chemists through the ages:

The physical chemists never use their eyes and are most lamentably lacking in chemical culture. It is essential to cast out from our midst, root and branch, this physical element and return to our laboratories.

Henry Edward Armstrong, 1848 to 1937

The country which is in advance of the rest of the world in chemistry will also be foremost in wealth and in general prosperity.

William Ramsay, 1852 to 1916

Time is the best appraiser of scientific work, and I am aware that an industrial discovery rarely produces all its fruit in the hands of its first inventor.

Louis Pasteur, 1822 to 1895

With monads and diads, and pentads and triads,
My brain has been addled completely;
And what’s really meant by ‘something-valent,’
Is a question I give up discretely.

John Cargill Brough, 1834 to 1872

The chemists are a strange class of mortals, impelled by an almost insane impulse to seek their pleasures amid smoke and vapor, soot and flame, poisons and poverty; yet among all these evils I seem to live so sweetly that may I die if I were to change places with the Persian king.

Johann Joachim Becher, 1635 to 1682

Chemistry, unlike other sciences, sprang originally from delusions and superstitions, and was at its commencement exactly on a par with magic and astrology.

Thomas Thomson, 1773 to 1852

Experimental science hardly ever affords us more than approximations to the truth; and whenever many agents are concerned we are in great danger of being mistaken.

Humphry Davy, 1778 to 1829

Chemistry begins in the stars. The stars are the source of the chemical elements, which are the building blocks of matter and the core of our subject.

Peter Atkins, 1940 to present

Still I had a lurking question. Would it not be better if one could really ‘see’ whether molecules as complicated as the sterols, or strychnine were just as experiment suggested?

Dorothy Hodgkin, 1910 to 1984

We think there is color, we think there is sweet, we think there is bitter, but in reality there are atoms and a void.

Democritus, c. 460 – c. 370 BC

Every aspect of the world today – even politics and international relations – is affected by chemistry.

Linus Pauling, 1901 to 1994

Chemists do not usually stutter. It would be very awkward if they did, seeing that they have at times to get out such words as methylethylamylophenylium.

Sir William Crookes, 1832 to 1919

I saw that people trying to synthesize gold and silver were working in ignorance, and by false methods; I then perceived that they belonged to two classes, the dupers and the duped. I pitied both of them.

Geber, c. 712 – c. 815 AD

A detective with his murder mystery, a chemist seeking the structure of a new compound, use little of the formal and logical modes of reasoning. Through a series of intuitions, surmises, fancies, they stumble upon the right explanation, and have a knack of seizing it when it once comes within reach.

Gilbert Lewis, 1875 – 1946

Chemistry is necessarily an experimental science: its conclusions are drawn from data, and its principles supported by evidence from facts.

Michael Faraday, 1791 to 1867

A fact acquires its true and full value only through the idea which is developed from it.

Justus von Liebig, 1803 to 1873

Nothing can be more certain than this: that we are just beginning to learn something of the wonders of the world on which we live and move and have our being.

William Ramsay, 1852 to 1916

Trial by combat of wits in disputations has no attraction for the seeker after truth; to him, the appeal to experiment is the last and only test of the merit of an opinion, conjecture, or hypotheses.

Joseph Mellor, 1869 to 1938

We must reason in natural philosophy not from what we hope, or even expect, but from what we perceive.

Humphry Davy, 1778 to 1829

You want bad ideas, but they have to be good bad ideas? You’ve come to the right place. First, a brilliant mathematician, who had already found one planet by sheer mind-power, and tried to repeat his success…

1. The Planet Vulcan

In 1859, Urbain Leverrier told the world that he had discovered a new planet, very close to the sun, which he called Vulcan.

He’d found that Mercury was not orbiting the sun the way Newton’s law of gravitation said it should: its perihelion advanced by about 0.01 degrees more than it ought to every hundred years.

That might not seem a lot, but Leverrier reasoned that a planet close to the sun was disturbing Mercury’s orbit.

Could it be Vulcan orbiting the sun?

He was taken seriously. After all, in 1845 he had used mathematics to analyze Uranus’s orbit and found that, like Mercury’s orbit, it was behaving slightly oddly. From this, Leverrier predicted the existence and position of a new planet. When astronomers looked to where he had directed them, they discovered… Neptune.

Funnily enough, after Leverrier published his incorrect Vulcan hypothesis, some astronomers, including Edmond Lescarbault, claimed to have seen it!

In the end, Vulcan was a mirage. The explanation for Mercury’s strange orbit came when Albert Einstein published his general theory of relativity.

Einstein showed that Newton’s law of gravitation is not quite right: the higher the gravity, the less accurate Newton’s law becomes. And Mercury feels the sun’s gravity strongest, because it’s the closest planet to the sun.

After Einstein published his relativity work, there was no need for Vulcan, which is a pity. A new planet is always exciting. And hey, if Leverrier had been right, Mr. Spock’s home planet would have been quite close to Earth, if a little on the hot side!

2. Polywater

In 1962, a new form of water was announced by the Russian physicist Nikolai Fedyakin. Polywater was denser, and more viscous than normal H₂O; it froze at -40 °C and boiled at 150 °C.

At the molecular level, polywater could have looked something like this

Perhaps this material consisted of water molecules bonded together into chains – a strange polymer of water. There was a lot of excitement in the scientific community at the time.

American scientist Dennis Rousseau found his own sweat had similar properties to polywater. By 1973 it was fully accepted that the water used in Fedyakin’s experiments had taken up impurities from laboratory equipment. As far as we know, there is still only one form of water.

3. N-Rays

N-rays were discovered in 1903 by Prosper Blondlot, a distinguished French physicist. He found that many metals were natural emitters of these rays.

His findings were confirmed in some other French laboratories, although physicists in other countries – including Lord Kelvin – were unable to observe N-rays.

American physicist Robert Wood was puzzled by these new, strangely elusive rays, and Blondlot agreed to give him a demonstration.

In a darkened room, Blondlot produced an ‘N-ray spectrum,’ which he discussed with Wood and other people who were present, showing them the spectrum’s interesting features.

While Blondlot was doing this, Wood secretly removed the spectroscope’s prism. This was like removing a prism being used to split sunlight into the colors of the rainbow. If you remove the prism, the colors disappear.

With the prism removed, Blondlot continued describing the N-ray spectrum as if nothing had happened!

Wood’s removal of the prism sent N-rays hurtling into science’s trashcan and sent Blondlot to the attentions of the medical profession. No kidding!

4. Darwin’s Theory of Evolution Disproved by Physicists

Darwin’s theory wasn’t attacked by cranks, but by two hard-headed physicists in Scotland.

Lord Kelvin (a brilliant physicist, whose name is remembered in the absolute temperature scale) and Fleming Jenkin thought they had proved Darwin wrong.

Kelvin looked at the cooling rate of our planet Earth. Using the best physics of the 1860s he estimated that Earth was somewhere between 20 and 400 million years old. For much of that time, he said, it would have been too hot for life. His calculations also showed it was ‘most probable’ that the Sun was less than 100 million years old.

Jenkin argued that Darwin’s theory required ‘countless ages’ to work, but Kelvin had proved that Earth’s age was ‘preposterously inadequate.’

Of course, Kelvin and Jenkin were wrong!

They didn’t know about nuclear fission which, after billions of years, still keeps Earth’s interior hot. They were also unaware of the nuclear fusion that has powered the Sun for billions of years. Nuclear energy had not been discovered in the 1860s.

If Kelvin and Jenkin had paid more attention to the evidence from geology and biology, they might have been in a position to propose radical new physical theories.

But, sadly, they didn’t!

5. Caloric

Why do things heat up? Until the end of the 18th century, scientists thought that ‘caloric’ needed to be released.

There was caloric in everything.

Flames would liberate the caloric from substances, causing a rise in temperature.

Anything which allowed a substance to release caloric – such as friction – caused the temperature to rise.

Seems sort of logical? Yes? Well… yes, until you think about it a bit harder.

Benjamin Thompson, also known as Count Rumford, realized that caloric was absurd. This happened when he was supervising a new cannon’s drilling-out in a workshop in Bavaria in 1798.

During the drilling, the cannon got very hot. Superficially, this seemed to fit the caloric theory as shards of metal were removed from the cannon by the drill, releasing caloric. The trouble was, when the drill got blunt and removed less metal from the cannon, the temperature rose even more. BUT, according to the caloric theory, the cannon should have cooled, because less caloric was being released.

Thompson found he could release heat from metal for a very long time (almost for ever) using a blunt drill. If this heat had come from caloric, then the metal must have contained so much caloric to begin with that it could never have cooled enough to become solid.

Rumford collected metal removed from the cannon and measured its specific heat. He found it was identical to the specific heat of unbored metal. He reasoned that it was movement rather than caloric causing the temperature rise.

Many scientists refused to abandon the idea of caloric. Despite the evidence against it, they clung to it like a comfort blanket.

It was only in 1849, when James Joule demonstrated how mechanical energy could be converted to thermal energy, and in 1860, when James Clerk Maxwell published his kinetic theory, showing that it’s the speed of atoms and molecules that determines a substance’s temperature that caloric finally faded away.

Click here for Part 2.