Page 156 - How It Works - Book Of Amazing Answers To Curious Questions, Volume 05-15

Who invented the

pencil sharpener?

Discover the French engineers and the The iconic ‘prism’
pencil sharpener
dates back to 1847
American tycoon behind the pencil sharpener
lthough the exact origins of the pencil The mechanism we’re familiar with today
are uncertain, its growing popularity came in 1847 from another Frenchman, Therry
Ademanded a far less time-consuming des Estwaux, who invented a cone-shaped
and far more precise method of sharpening it device with a single blade that when turned
than to slash away with a knife. would neatly and evenly shave away at the
The first attempt came in 1828 from French pencil on all sides.

mathematician Bernard Lassimone, who The French may have paved the way, but it
placed two blades at 90 degree angles on a was America that made waves. In the 1850s, US
block of wood, but this method of grinding inventor Walter K Foster mass-produced a
down the pencil to a point wasn’t any faster similar cone design and by 1857 his company
than the traditional method. was cranking out 7,200 sharpeners a day.

When did the

‘butcher crocodile’

roam Earth?

The ‘Carolina Butcher’ topped the
food chain 231 million years ago

hen the supercontinent Pangaea was breaking
apart, 2.7-metre (nine-foot) tall, sharp-toothed
Wcreatures roamed the area that would become
North Carolina in North America. Palaeontologists have
recently discovered parts of the skeleton belonging to
Carnufex carolinensis, an ancestor of today’s crocodiles.
Nicknamed the ‘Carolina Butcher’, it is believed to have
used its blade-like teeth to slice flesh from its prey,

likely to have been armoured reptiles and the early
relatives of large mammals. As its forearms were
so short, it is also suspected the creature
walked on two legs, much like a T-rex.

© Corbis; Jorge Gonzalez; NASA

A 3D model of the
creature was created
from scans of its fossils

156 How It Works