At first this was the width of a man’s thumb. ​

In the 14th century, King Edward II of England released an order that one of this was equal to 3 grains of barley placed end to end lengthwise.​

What unit of length is being described here, that is even used today?​

The use of this to accurately measure time was discovered by Galileo Galilei around 400 years ago.​

 It is a free-swinging weight hanging from a pivot that moves left to right. ​

What did he use?

This unit of measurement was used by the Ancient Greeks to measure the distance from the tip of the thumb to the tip of the index finger.​

It also means the action of passing the tongue over a surface. ​

What old unit of measurement now nonexistent are we talking about?

This is one of the earliest type of timekeeping device. It indicates the time of the day by the position of the shadow when exposed to the sun’s rays.​

As the day progresses and the sun moves across the sky, it casts the shadow which also moves along its dials, indicating the passage of time.​

What are we talking about?

Shown here is Daniel Gabriel Fahrenheit, a German physicist who dedicated his life to science and inventions.​

He is credited with the invention of the modern version of a certain instrument that is found mainly in hospitals.​

What did he invent that revolutionized medical science forever?

Friedrich Ludwig Jahn is credited with the invention of this device.​

It is used to compare the mass of two objects. There is a fulcrum alongside which the objects rest and then the mass is measured.​

Which device are we talking about?