The whole of metallurgy is determined by the fact that molten metals have a very low viscosity. Casting them is easy and simple. Some metals can be forged as solids, by raising them to a temperature at which they can readily be deformed. But molten metals are not easily blown or drawn like glass, or spread like tarmac, or vacuum-formed like plastics. Such processes would need a metallic melt that was viscous and tacky. So Daedalus is inventing one.

What is needed, he says, is some sort of long-chain polymer that will dissolve in the molten metal without decomposing. Even in very low concentrations, it would thicken the melt dramatically, as linear polymers do in solution, or fine fibres in suspension. At first sight the chemistry looks discouraging. Organic polymers decompose at the temperature of most molten metals, and silicones would be immiscible with them. Some sort of long-chain silicone molecule with metallic side-chains might be feasible. But the obvious answer is that modern solution in search of a problem, the carbon nanotube.

Many alloys, especially those of iron, contain carbon inclusions, so problems of compatibility should not arise. Carbon nanotubes have a high (indeed, unknown) melting point. They have been filled with molten metal, so are clearly wetted by it; they can be made in micrometre sizes like chain-polymer molecules, and they are immensely strong. They are certainly expensive, but are rapidly getting cheaper. In any case only a small concentration of them should transform a runny molten metal into a viscous liquid. The resulting product should transform metallurgy.

The most immediate application would be to those shell structures — cans, boxes, containers, car-bodies and so on — which are now pressed or fabricated from sheet. An alloy which could be blow-moulded like glass would make it possible to form such products in one simple, effortless operation. Similarly, wire could be drawn in the finest sizes by simple melt-pulling, like glass fibre. Thin-wall metal tube and sheet could be blown continuously, like plastics layflat tubing. Light, strong metal foam or insulating and resilient metal wool could be made by blowing gas into the sticky melt at a well-judged velocity. Better still, all the resulting products could easily be repaired or modified with a simple blow-torch. Heated to tackiness, they could be annealed, augmented, deformed, or teased into new shapes by the skills of the traditional glassblower.