The Second Book of General Ignorance

There are various accounts of humans growing ‘horns’ of the non-bony type. One of the strangest concerns Anna Schimper, ‘the horned nun of Filzen’. In 1795 her nunnery in the Rhineland was occupied by French troops and the nuns evicted. The shock sent Anna mad and she was committed to an asylum. After years spent banging her head against a table, a horn started to grow from the bump on her forehead. The more it grew, the less deranged she became until she was soon sane enough to return to the nunnery, where she became abbess.
By 1834 her horn had grown to such a length that it was hard to conceal under her wimple, so she decided to have it removed. Although she was eighty-seven and the operation was both bloody and painful, she survived and lived for two more years. By the time she died her mysterious therapeutic horn had started to grow again.

The polar food chain is based on marine algae that are rich in vitamin A. The further up the chain you go, the more it concentrates. Huskies – like seals and polar bears – have evolved to cope with it. Humans haven’t. There is enough Vitamin A in just 100 g (3½ ounces) of husky liver to kill a grown man.

True horns have a permanent bone core surrounded by compacted strands of a protein called keratin – the same stuff that human hair and nails are made from. Animals that have them include cattle, buffalo, sheep, antelopes and horned lizards.

a metal is simply defined as something that conducts electricity and heat. Of the 118 elements known, only eighteen are non-metals.

y the time the Egyptians worked out how to make glass, the Chinese had been drinking tea (traditionally they began in 2737 BC) for almost 1,400 years. Its colour was less important to them than temperature, and they found it was best served in their most famous invention of all: fine porcelain, or ‘china’.

1350 BC, but it was the Romans who first produced transparent glass. They liked the way it enabled them to admire the colour of their wine.

The impact of high-grade glass on Western culture cannot be overstated. The invention of spectacles towards the end of the thirteenth century added at least fifteen years to the academic and scientific careers of men whose work depended on reading. The precise reflection of glass mirrors led to the discovery of perspective in Renaissance painting. Glass beakers and test tubes transformed ancient alchemy into the modern science of chemistry.
The microscope and the telescope, invented within a few years of each other at the end of the sixteenth century, opened up two new universes: the very distant and the very small.
By the seventeenth century, European glass had become cheap enough for ordinary people to use it for windowpanes (as opposed to mere holes in the wall or the paper screens of the Orient). This protected them from the elements and flooded their houses with light, initiating a great leap forward in hygiene. Dirt and vermin became visible, and living spaces clean and disease free. As a result, plague was eliminated from most of Europe by the early eighteenth century.
In the mid-nineteenth century, transparent, easily sterilised swan-necked glass flasks allowed the French chemist Louis Pasteur to disprove the theory that germs spontaneously generated from putrefying matter. This led to a revolution in the understanding of disease and to the development of modern medicine. Not long afterwards, glass light bulbs changed both work and leisure forever.

What a sauna can do well is clean your skin, by opening your pores as you sweat. A fifteen-minute session at a temperature of 70°C and 40 per cent humidity raises the body’s surface temperature by 10°C and its internal temperature by 3°C. This increases blood flow to the skin and makes the lungs work harder, increasing the intake of oxygen by up to 20 per cent – which is why endurance athletes often use saunas as part of their training.

true that it’s not a good idea to drink heavily on antibiotics, because the alcohol competes with the drug for ‘processing time’ in your liver. This means the drug may work a little more slowly. What it won’t do is stop it working altogether.

Metronidazole, which is used to combat some dental and gynaecological infections and for treating Clostridium difficile, a bacterial infection picked up in hospitals. The drug prevents the body from breaking down alcohol properly, leading to a build up in the blood of the highly toxic chemical acetaldehyde