Pencil: with eraser

The first person to attach an eraser to a pencil was Hymen Lipman, on March 30th 1858, in the USA. It is such a good simple idea.

The metal band which connects the eraser to the pencil is a ferrule
The metal band which connects the eraser to the pencil is a ferrule
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Pencil: wooden holders

The first people to make wooden holders for black graphite pencils were an Italian couple, Simonio and Lyndiana Bernacotti, sometime around 1560. They were carpenters and they used juniper wood to make a compact, flat pencil.

Shortly after a better way was found using two semi-circles of wood, which were glued together. This is basically the same method that is still used today. The two methods are shown in the drawings below.

You can now make your own pencils
You can now make your own pencils

Pencil: graphite

The black stuff that is used in pencils is graphite.

This graphite would make a few pencils
This graphite would make a few pencils

Graphite is actually pure carbon. It is like top quality coal.

Some time after the year 1500 a huge amount of pure graphite was discovered in the north of England. The local people realised that this graphite was very special stuff.

At first graphite sticks were found to be very good for marking sheep, but soon they were also used for writing on paper. To stop the fingers from getting black the graphite sticks were wrapped in string, or even sheepskin.

News of these early pencils spread fast, attracting artists from all over the world.

Pencil: original

The original pencil was just a thin, metal stick, which was used for scratching shapes and letters on to papyrus, which was an old type of paper. This was done by the ancient Egyptians and Romans, and the word ‘pencil’ comes from the Latin (Roman) word ‘pencillus’ which means ‘little tail’.

Ancient writing on papyrus paper
Ancient writing on papyrus paper

Who invented the eraser?

This question came up in one of my classes.

Mistakes are good!
Mistakes are good!

So who invented the eraser?

Before the eraser, wax, or even bread, was used to erase pencil marks.

On April 15th 1770 the famous British scientist Joseph Priestley wrote that a vegetable gum, which he called rubber, was very good for erasing black pencil marks. So it is thought that Priestley discovered that rubber is for good for erasing.

But it is later in 1770 that Edward Nairne, a British engineer, first manufactured and sold the rubber eraser. Therefore Nairne is thought to have invented the eraser.

100 trillion dollars

You can buy this on e-bay
You can buy this on e-bay

Sounds a lot of money, doesn’t it? 100,ooo,ooo,ooo,ooo dollars.

This is a picture of the old 100 billion note, and some of the other denominations.

A fortune?
A fortune?

But this is Zimbabwe. 100 trillion Zimbabwe dollars are worth about 30 US dollars. This is no joke. A loaf of bread costs about 50 billion dollars today, and tomorrow it will cost about 100 billion dollars.

The money is heavier than the shopping
The money is heavier than the shopping