Here must be mentioned another form of hydrogen, named tritium. It has long ago disappeared from nature but it is now being re-created in ponderable amounts in our atomic furnaces. Tritium, the nucleus of which is known as a triton, weighs three times as much as the lightest form of hydrogen. It has an energy content nearly twice that of deuterium. But it is very difficult to make and is extremely expensive. Its cost per kilogram at present AEC prices is close to a billion dollars, as compared with no more than $4,500 for a kilogram of deuterium. A combination of deuterons and tritons would release the greatest energy of all, 3.5 times the energy of deuterons alone. It would reduce the amount of tritons required to half the volume and three fifths of the weight required in a pure triton bomb, thus making the cost considerably lower. But why bother with such fantastically costly tritons when we can get all the deuterium we want at no more than $4,500 a kilogram, while we can make up the difference in energy by merely incorporating two to three and a half times as much deuterium? Here we are dealing with what is probably the most ticklish question in the design of the H-bomb. To light a fire successfully, it is not enough merely to have a match. The match must burn for a time long enough for its flame to act. If you try to light a cigarette in a strong wind, the wind may blow out your match so fast that your cigarette will not light. The same question presents itself here, but on a much greater scale. The match for lighting deuterium—namely, the A-bomb—burns only for about a hundred billionths of a second. Is this time long enough to light the “cigarette” with this one and only “match”? It is known that the time is much too slow for lighting deuterium in its gaseous form. But it is also known that the inflammability is much faster when the gas is compressed to its liquid form, at which its density is 790 times greater. At this density it would take only seven liters (about 7.4 quarts) per one kilogram (2.2 pounds), as compared with 5,555 liters for gaseous deuterium. And it catches fire in a much shorter time. Is this time long enough? On the answer to this question will depend whether the hydrogen bomb will consist of deuterium alone or of deuterium and tritium, for it is known that the deuteron-triton combination catches fire much faster than deuterons or tritons alone.