"HEAVY WATER"

Evening Post, Volume CXVIII, Issue 34, 9 August 1934, Page 20

"HEAVY WATER"

TO BE MADE FOR SALE

ONE TEASPOONFUL A DAY

GREAT POSSIBILITIES

Professor G. N. Lewis discovered "heavy water" in California in July, 1933. It looks like proving to be one of tho most important scientific triumphs of recent-years (says tho "Manchester Guardian").

Tho mniounecmcnt that Imperial ;i Chemical Industries are to manufacture ' "heavy water" commercially will bo 2 of great interest to scientists throughi out tho world. It opens up opportuni--3 tics for research in chemistry, in bioI logy, in medicine, and in many other fields where, so long as the new product remained a laboratory curiosity, 1 such opportunities could not exist, l The discovery of a new form of - hydrogen and of its derivative, "heavy : water," has been described as the great- ' est American achievement in physical 5 seicueo since that Michelson-Morley ox- ' periment of 1887 which prepared the ' way for the theory of relativity. It showed that hydrogen, one of the basic elements of matter, was 'not a simple substance; that'even such apparently unchanging stuff as water could exist in nine different forms; and that, besides the vast number of known compounds into which hydrogen enters, there must bo a vast potential number hitherto undreamt of. To produce these and discover their properties will take generations. Whatwil-1 those properties be? Are we to have new and better fertilisers, dyes, soaps, and scents, drugs as revolutionary as chloroform, new and more devastating explosives? Little is known at present of "heavy water" except that it kills tadpoles and that the seeds of some plants cannot live in it. The decision of Imperial Chemical Industries to'produce it for sale is an act which should have its reward when its uses are discovered. At present it has no employment outside the laboratory. PKICE UNKNOWN. No information is available about the probable price. But in difficulty of production and in the tremendous disparity between the volume of the raw material and that of the finished product "heavy water" is comparable with radium. The vast resources of electrolysis available at the Billingham factory are expected to produce an initial output of a teaspoonful a day. It will be a precious tcaspoonful. It is explained that the heavier isotope exists only in small proportion (about one in 6000), but preparations of water in which the hydrogen isotope of mass one is replaced by the isotope of mass two can now be obtained. The density of this water is found to be about 10 per cent, greater than that'of '■ ordinary water, and though in no way differing from ordinary water i in outward appearance, certain of its I physical and chemical properties show marked differences. Thus, its freezing point is 3.Bdeg. Centigrade, its boilingpoint is lOSdcg. Centigrade, and its refractive index is notably lower than that of ordinary water. Terrestrial sources vary in their content of "heavy water." Rain water is weakest in it, ordinary iriver and lake water contains one part in GSOO, sea water one part in 5000, .while certain electrolytic residues have been found to contain as much as one part in 2700. . : Most of tho research work on "heavy water," asserts the "Yorkshire Post," has so far been done in the United States, whero it was discovered last year. Now it should bo possible for.: Great Britain- to take a loading place in this entirely new field of research, which seems certain to yield a rich harvest, particularly for chemistry and biology. TWICE AS HEAVY. "Heavy water," like ordinary. water, consists simply of hydrogen and oxygen, but the hydrogen which enters into its composition is not ordinary hydrogen for each of its atoms is twice as heavy as the normal hydrogen atom. Many elements are known to consist of these mixed atoms, which are said to give rise to different "isotopes" of the element, and tho existence of hydrogen "isotopes" has been suspected for some years. It was also known that they would bo likely to have exceptional properties, for an ordinary hydrogen atom is the lightest of all atoms, and the addition to it of an extra unit would double its mass. "Heavy "water" itself was discovered through cxepriments with electrolysis, based on the idea that when water is split up by an electric current the ordinary hydrogen atoms would, pass through the water at a higher relative speed, leaving an excess of heavy atoms in the remaining liquid. These experiments succeeded; and eventually its was deduced that out of every 6500 hydrogen atoms in ordinary water one atom is of the heavy variety. The next step was to isolate the heavy constituent, and as soon as this was done the remarkable properties of heavy water began to be apparent. For instance, it was found that heavy water was quickly lethal to seeds and primitive forms of animal life, and there is evidently a great deal of work to be d.ono in studying the influence of heavy water on all sorts of biological process. WE DRINK IT. Whenever we drink a glass of water we consume a minute proportion of heavy water, and the effect of this on the human organism is not yet known. Further, heavy water or —rather, the heavy hydrogen atoms found in itwill probably prove a powerful weapon in. physical and chemical research. The heavy hydrogen atom has already been used as a projectile in atomic disintegration experiments, providing physicists with artillery, so to speak, of a higher calibre. One reason for its value to chemists is that hydrogen enters into more compounds than any other element. The discovery of heavy hydrogen means that tho number of hydrogen compounds is, xor may be, doubled; and the comparison of two compounds, one formed tj from ordinary hydrogen and the other :■ from heavy hydrogen, is expected to i throw valuable light on molecular struc- 1 ture. I Quite recently a third hydrogen ■', isotope, of triple weight, has been dis- ■ covered, and there arc known to bo at j' least thrco isotopes of oxygen. Water '■' is thus not a simple uniform substance, but a 'complicated mixture or nnmlgnm ; of numerous substances, each, no doubt, i possessing distinctive characteristics. |i

It is recognised that, since "United States scientists discovered heavy hydrogen, they have a certain right to name it; but a serious objection to "deutron" is that it is very like "neutron" —the recently-discovered particle carrying no electric charge—and when the two words are spoken by a scientist afflicted with a cold in the head they are apt to sound indistinguishable. Now, as a name for the triple-weight hydrogen atom, the United States is suggesting "tritium" and Great Britain "triplogen." An International Physics Conference is to be held in England next autumn, and perhaps these controversies will then be settled.

They show that scientists, after all, arc human; but heavy hydrogen is clearly so valuable a discovery that research into its properties ought not to l>p confused by iiny trivi.'i] dispni'' uvor names.