As luck would have it, Dr Borra came across a suitable class of materials.

ECONOMIST: Mirror, mirror

One of the leading proponents of the liquid-mirror approach is Ermanno Borra, a physicist at Laval University in Quebec.

ECONOMIST: Mirror, mirror

LMTs, Dr Borra is doing his best to overcome their inability to point.

ECONOMIST: Mirror, mirror

Dr Borra worked out just how viscous the liquid would need to be, and found that it had to be the consistency of thick honey.

ECONOMIST: Mirror, mirror

By far the most famous exponent was a bushy-haired Serbian named Borislav Milojkowic, who went by the stage name Borra, King of the Pickpockets, and became a star of night clubs and circuses throughout Europe.

NEWYORKER: A Pickpocket��s Tale

So far, Dr Borra has achieved a reflectivity of 50% (that is, half of the light falling on the mirror is reflected), but he is confident that he will be able to equal the 80% reflectivity of mercury.

ECONOMIST: Mirror, mirror