At night, the outside of the cave was pitch black, and the rain could be faintly seen hanging from the mouth of the cave like a waterfall by the light of the fire.

In the dark night sky, occasionally a thick lightning bolt pierced the sky and landed in the jungle in the distance, and I don't know how many trees were turned to ashes on this rainy night.

People were so tired that even though the thunder was roaring outside, people still fell asleep peacefully.

In the early morning, the rain weakened, and the raindrops dripped intermittently on the puddle at the entrance of the cave with a soft sound.

After a night's rest, although the muscles on the body are still a little sore, people's tired bodies have been relieved a lot.

When people walked out of the cave, the sight below the mountain turned people's faces extremely pale.

Floods, with no end in sight, surging floods that knocked down trees, rolled up dirt and stones, and a large number of animal carcasses rose and fell in the filthy current, and there was a faint fishy smell in the air.

Looking at the flood of this scale, Wang Lang couldn't help but secretly rejoice, if they didn't come to this valley in time, then they would also be swallowed by this terrifying current and become one of those corpses on the water.

The bottom of the mountain has become an ocean, and people can't do anything to go down the mountain, so they can only stay on the mountain until the flood waters recede.

On another mountain not far from the cave, a large area of landslides occurred, the soft soil on the surface of the mountain was washed away by the rain, a large number of plants were buried in the soil, and the rocks under the soil layer were bare and exposed.

"Lang, Lang, come and see what this is!" An exclamation rang out from inside the cave.

People looked back in amazement to see the stars and a few women curiously stirring with the ashes on the ground with branches.

People walked over curiously, not knowing what was all the fuss about a pile of useless ashes.

As the ashes were gradually removed, I saw that there was a layer of white substance covering the rocks below, Wang Lang looked at these silvery-white things, his eyes lit up, this thing was obviously some kind of metal, Wang Lang first reflected that this was silver, but then denied it, these things were obviously formed after melting, and his chemical knowledge had not been completely returned to the teacher, and the melting point of silver should not be so low.

Wang Lang squatted down and buckled the white substances with his hands, these things were very strong and stuck to the rocks, Wang Lang picked up a stone and knocked it hard, making a "dangdang" sound.

Only a few small uneven pits were left on its surface.

"Make a fire, make a fire!" Wang Lang shouted excitedly, if he didn't guess wrong, this thing must be tin. This is the first metal I found in this world, and I am naturally very excited.

People looked at each other, but although the thing looked beautiful, Wang Lang had been very calm since he was the leader, and he didn't know why he was so out of shape this time.

Seeing that people didn't take action, Wang Lang said dissatisfiedly: "What are you doing in a daze, this thing is a baby, hurry up and make a fire." ”

Hearing that it was a baby, people suddenly came to their senses, and every treasure that Wang Lang said brought great benefits to the tribe.

Fire is the best at making fire in the tribe, after hearing Wang Lang say baby, his eyes lit up, not to mention finding something to start the fire, the dry wooden stick rotated quickly in his hand, it didn't take long for the front end of the wooden stick to appear due to friction spark, the fire carefully took the wooden stick to the side of the prepared hay, and kept blowing, it didn't take long for the hay to rise up smoke, and after a while, the flame rubbed up.

After the fire was lit, Wang Lang picked up some rubble scattered in the cave and said that they threw it into the fire.

In the scorching flames, only some of the mixed silvery-white stones slowly cracked, and the rest did not change in the fire.

With the continuous heating, the liquid of those silver-white stones slowly flowed out, and Wang Lang almost couldn't close his mouth when he saw these silver-white metal solutions.

"Metal! It's metal, and even the worst metal is infinitely better than stone! Wang Lang was ecstatic.

When Wang Lang was in school, he heard from his teacher that the earliest metal discovered by mankind was tin, and it was precisely because of the low melting point of tin that there was no need to build any kiln to smelt, and only needed to use ordinary flame calcination to melt them.

People watched these miraculous stones turn into liquid in the flames, and their mouths opened wide in disbelief.

Although the texture of metal tin is relatively soft, and it is not even as hard as stone, this thing is an indispensable thing for future development, as long as copper ore can be found in the future, you can add this metal to refine bronze, as long as bronze appears, you will have no opponents in this world.

Although tin is softer, it is more malleable as a metal than stone, and can be used as an arrow spearhead as long as it is polished, even if it is blunt, it can be extremely sharp when sharpened.

Thinking of this, Wang Lang, who was very excited, hurriedly ran to the outside of the cave, found some yellow mud on the hillside, and after bringing these things back to the cave, Wang Lang picked out the gravel in the yellow mud and took a little water and poured it on the mud.

People looked at Wang Lang as if he was going to fire pottery, and they couldn't understand what Wang Lang was going to do, but looking at his excited appearance, they also knew that this must be a very important thing.

"Fire, bring an arrow and a spear!" Wang Lang said without raising his head.

When the fire heard this, he immediately took an arrow from the skin quiver and handed it to Wang Lang, and put a stone spear beside Wang Lang.

Nowadays, the arrows used by people are extremely rudimentary, the arrows are polished with triangular stone chips, and a groove is carved at the top of the arrow shaft, and the stone is stuck in the groove and tied with a rope.

Wang Lang didn't plan to make such arrows out of metal, it would be a waste to do that.

Wang Lang put the reconciled mud on top of a relatively flat stone, used the straight spear shaft as a rolling pin, pressed the yellow mud into a cake the size of a palm five or six centimeters thick, and then used a stone knife to cut the thing into two rectangles of about the same size.

Next, Wang Lang used an arrow shaft to press a semicircular groove on the edge of each of the two pieces of mud, then used a piece of wood to carve two scratches of a few millimeters along the shape of the groove, and then used a piece of wood to carve a conical shape at the top of the groove, and finally sealed the top of the groove with a pinched piece of clay.

After doing this, Wang Lang put these two simple molds into the fire calcination, it stands to reason that it is more ideal to fire pottery, but in today's situation, Wang Lang is not in a position to do such a complicated thing, as long as the two clay tablets are burned hard, they should be able to be used.

Half an hour later, the template was successfully fired, although there were some cracks, but it did not affect the use, Wang Lang used a stone knife to polish the clay tablet flat, and put the two clay tablets together, but this purely handmade thing is not very accurate, and there is an error that can be seen with the naked eye.

Wang Lang didn't care about this, as long as he could make arrows, it would be easier to polish with the characteristics of metal tin, and if it was any other metal, this thing made by Wang Lang would be almost useless.