Much Ado About (Practically) Nothing: A History of the Noble Gases

The noble gases are the silent onlookers of the chemical world. Atoms of helium, neon, argon, krypton and radon have electrons, in the negatively charged cloud smeared around their nuclei, in just the right numbers for stability. Disposed neither to gain nor lose electrons - the two drivers of chemical interaction - they do not combine. They are, in the more common descriptor for the group, inert.

Their inertness meant they eluded discovery while the roster of elements was being filled in. The first, helium, was spotted in the absorption spectrum of sunlight in 1868, although it took another 25 years to find it on Earth. The rest were all identified by the British physicist Lord Rayleigh and the chemist William Ramsey. Their first collaborative discovery was argon, present in tiny amounts in the air. Ramsey recognised that helium and argon were two members of a new group in the recently established periodic table, and by 1900 had found and named all the rest.

It is a fairly simple story, and told in a chapter of David Fisher's book. For, despite the subtitle, it is not a history of the noble gases, but a look at their uses. Their very inertness has led to lots of practical uses, from helium balloons to neon lighting and, in the case of xenon, as an anaesthetic. But Fisher is more interested in their scientific possibilities, seen mainly through his own life as an experimenter.

He is an engaging writer - in addition to a professorial career at Cornell University and the University of Miami, he has produced novels, plays and many non-fiction books - and offers an agreeable read. The result is a close look at the life of a middle-ranking US scientist in the second half of the 20th century. The style is super-cheery in places - "Alexander the Great: what a guy!" - but easier to live with once he gets into his stride. The content is mixed. It includes lots of laboratory lore, biographical snippets about other scientists (some of dubious relevance), a few historical howlers when he is out of his own field, and more personal digressions about departmental politics and life in the US, which are at best mildly interesting.

Still, it meanders its way to an informative composite picture of what this particular scientific life was like. Pretty fortunate, is the overall impression. Fisher benefited from a post-war research boom, which, strange to relate, included days towards the end of the 1960s when the National Science Foundation phoned to say "they had $200,000 left over from their budget, and did anyone want it? No one did, we all had enough money."

If money was easy, science was still hard. The best chapters focus on Fisher's own work, usually trying to use noble gas traces to read the history of minerals. They came from meteorites, from the ocean floor, or from deep inside the Earth. The common feature is that careful measurements of the ratios of unusual isotopes - where one of a pair of related atoms is either created by cosmic ray bombardment or is the product of radioactive decay - can be used to measure the age of specimens.

The principle is simple, the practice intricate and delicate. Things frequently go awry. The assumptions behind each measurement are complex, and may be proved wrong. The physical separation and chemical analyses, which often use noble gases because they are normally present only in small amounts so new production gives a clearer signal, were arduous. And work often followed false trails and mistaken hunches. Quite often, the experiments did not come to any particularly useful conclusion, but simply petered out. This is real research, seen through the stories that scientists' histories of science usually leave out. Fisher tells them well.