That day, a building in the university caught fire. "Boo hoo" fire truck rushed to the scene.

A strange thing happened: the fire brigade wanted to get tap water from a nearby building. However, the police are at the gate of the building.

Security measures are very strict, and firefighters are not allowed in.

"Burning eyebrows, don't let us in?" The fireman asked anxiously.

"No way. No one can enter without the certificate of the Ministry of National Defense! " The guard said with a livid face.

The fire was fierce and the firemen were in a hurry. They surrounded the guards and asked loudly, "When the Ministry of Defense's certificate arrives, the building."

It's burnt out! "

The doorman finally made some concessions: "well, you go to the local X Bureau for instructions and make a proof."

No way, the firemen had to drive the fire truck to the X Bureau to get the license.

The firemen stuffed their papers into the hands of the guards and hurried to the building.

At this time, the guards caught up with them and stopped them. He said very seriously, "gentlemen, although you have the evidence, you should follow it."

It is stipulated that everyone who enters the building should sign the register. Gentlemen, please sign! "

The firemen laughed and cried, so they had to return to sign.

Although these guards are so loyal to their duties, they still reveal the secrets of the building. People suspect that the building is heavily guarded.

It's tight What's in it?

You know, the U.S. Department of Defense took great pains to keep the building secret: once, security guards carefully inspected the building.

In the library in the building, I found that many chemistry books look relatively new, but the chapters about elemental uranium in each book have been turned over.

Roll up the corner of the book, or it will get dirty. The security guard thinks that these books may also lead to the leakage of the secrets of the building and decides to destroy them all.

I also bought a batch of brand-new chemistry books. They were so careful to keep a secret that they accidentally got caught in a fire in the building next door.

Exposed.

As a result, German spies began to pay attention to this building. ...

Needless to say, the scientists in that building are studying the chemical element uranium in great secrecy.

Why is uranium research so strictly confidential?

1On August 5th, 945, the explosion of the atomic bomb shook the world. The "protagonist" in the atomic bomb is uranium. Because of this,

That building has become a key secret department of the U.S. Department of Defense and the focus of German spy agencies.