Drops of Prince Rupert

“Dutch tears” or “Batavian tears” are an illustration of one of the interesting properties of glass. It's popularly to call them "drops of Prince Rupert." Making a drop of Prince Rupert is not difficult. Simply take the red-hot glass and drip it into a bucket of water. Water quickly cools the outer surface of the glass, while inside the temperature remains high. When the glass finally cools inside, it shrinks inside the already solid outer shell. This creates a very strong strain.

Drops of Prince Rupert

 Interestingly, such a drop has tremendous durability! Unlike ordinary glass, the drop cannot be broken even by striking it very hard with a hammer - if you hit the main part of the “drop”. It can not be crushed by the press. However, if you slightly damage the “tail” of the tear, it explodes like a grenade. True, this process can only be seen with a camera capable of shooting at a speed of 100,000 frames per second.

The Drop of Prince Rupert

Prince Rupert showed interest in scientific experiments, he was one of the founders of the Royal Society. In particular, the prince experimented with the production of gunpowder (the method he proposed made gunpowder 10 times more efficient than Chinese), tried to improve guns, invented an alloy known as “Prince's metal”, and also developed a device for, so to speak, deep-sea diving, tried to improve surgical tools and was the author of outstanding engravings. As for the Botava Tears, most likely, such glass drops had been known to glassblowers since time immemorial, but they attracted the attention of scientists quite late: somewhere in the middle of the XVII century. They appeared in Europe (according to various sources, in Holland, Denmark or Germany). They were brought to England by Prince Rupert of Pfalz, which is why they began, following somebody's example, to be called Prince Rupert’s drops.