Daqin Engineers

This can't wait for the beginning of spring next year.

It's not that Qin Jun will not be able to besiege the city until next year, but that there are too many variables.

Will the Chu army come to help during the siege?

Did Wei Wangcao change his mind and go out of the city to fight?

If it were the combination of Chu and Wei, then Qin Jun would really be unable to deal with it.

So Ye Changmeng should have a quick fight.

But what can be done about this situation?

The first and second paragraphs are fortunate to say that the Qin army organized tens of thousands of people to clear the silt, which can be completed in three or five days.

But the third paragraph under the beam of Liangcheng...not to mention three or five days, it is a question of whether the three or fifty days can be cleared.

Shen Bing, who has been silent for a long time, made a suggestion:

"Can the first two sections be dredged and the third section built a dam?"

This is actually easy to understand.

If there is silt blocking the river course and the river overflows to the side, use dams to block it on both sides.

In fact, there is no need to block "both sides", because the other side is Daliang City, that is, just block the side far away from Daliang City.

But how could Zheng Guo not think of such a simple question.

Zheng Guo replied:

"Building a dam may be feasible."

"But the dike still has to be built under Daliang City, and it will take longer. Doesn't it mean the gains outweigh the losses?"

What this says is.

We must know that the range of crossbows in this era has more than 100 steps, and the range of trebuchets can even reach two hundred steps.

It is true that you do not need to go directly to Daliang City to build a dam, but it is not far away.

If the dam is built far, say, a hundred steps away, and there is not enough water to pose a threat to Daliang City...

So to come and go, you still have to work under the blows of Wei Jun’s crossbows, which is not much better than digging river mud to dredge.

Shen Bing didn't understand a question, so he asked curiously:

"Why does it take longer to build a dam?"

Yang Duanhe and Zheng Guo met with strange glances at Shen Bing.

Isn’t it well-known that it takes longer to build a dam?

But it turns out that two methods are commonly used to build dams in this era:

One is to build stones along the river bank.

The other is to fill it with wood and rammed earth, and then pound it.

Otherwise, if the soil is too loose, the river will collapse as soon as it flushes.

Neither of these two methods of dam construction are fuel-efficient.

Build stones?This involves the problem of moving stone and laying solid.

Wood rammed earth?The pounding of logs and rammed earth takes time.

It would be okay to do this in other places, but to do it under the range of Wei Bing's crossbow... undoubtedly it would be fatal.

So like Zheng Guo said, it is more difficult and troublesome than dredging and digging mud.

Shen Bing asked suspiciously:

"Why don't I wait to fill out a temporary dam with sandbags?"

"Anyway, this dam does not need to last long, just a few days of flooding the girders!"

Zheng Tong could not help but wonder:

"Sandbag? What is a sandbag?"

Shen Bing secretly said that there were no sandbags in this era, so he explained:

"It's actually a sack."

"It is called a sandbag if you fill it with sand!"

Yang Duanhe looked dumbfounded.

Zheng Guo said "Oh", his eyes widened and said:

"It's'grass wrapped in mud'?"

"Sister-in-law mean...make'grass wrapped in mud' with sack?"

"good idea!"

It turns out that there were no sandbags in ancient times, but everything in this period was artificial, even the hemp rope was twisted one by one, and the sacks were woven by hand.

It is usually used to carry grain, for example, many sacks are needed to transport military rations.

Its production is difficult and the output is small, so of course it will not be filled with sand and then thrown to the river... It becomes a small piece of the temporary dam.

The method used by the ancients to block water was what Zheng Guo called "grass wrapped in mud".

It uses reed, thatch or wheat stalks to wrap clay into a cylindrical shape, and then tie it with twine to make a sandbag.

The advantage of this kind of sandbag is that it does not need to use sacks, so it is very cheap. The disadvantage is that the water blocking effect is not good and it is affected by the season and region.

For example, it is difficult to put stones or sand inside without leaking, and it is still easily washed out by water.

Another example is that in winter, there are fewer reeds and thatch, and most wheat stalks are burned in farming. At this time, it is not easy to find a large amount of raw materials to make, and it also requires a lot of manpower and time to make.

So Zheng Guo didn't think of this method, but this method is unavailable or useless.

At this moment, when Shen Bing heard about sacks, he couldn't help but nod slowly.

Yang Duanhe asked curiously:

"Listen to my husband, can this sandbag be used to build a temporary dam?"

"And can it be done in a short time?"

In order to explain better, Shen Bing simply ordered dozens of sacks to demonstrate.

Shen Bing said as he directed the craftsmen to work:

"I can fill the sacks with sand first."

"It depends on the situation."

"For example, near the outer edge of the river, you can use sand and gravel that are not easily scattered in the water."

"The inner edge uses more stable rammed earth."

"Tighten the mouth of the bag when it is full, and stack the dike where it needs to be built!"

As I said, I saw the craftsmen stack dozens of sandbags in a row, forming a dam in a short while.

After finishing, Shen Bing added another sentence:

"In the meantime, if it is tied with wooden stakes and twine, it will be stronger!"

Yang Duanhe looked at Zheng Guo, as if asking Zheng Guo if this method was feasible.

Zheng Guo nodded affirmatively and replied:

"This method is feasible, this method is feasible."

"This sandbag looks like'grass wrapped in mud', but it's not known how many times better than'grass wrapped in mud"!"

"The sack can hold the sand and stone together firmly without loosening it. Although the water blocking effect is not as good as that of a dyke, it is not weak."

"Unless the sacks have been soaked and rotted and cracked for a long time, otherwise this dam..."

After thinking about it, Zheng Guo said:

"Why don't I wait and try?"

Yang Duanhe asked:

"How to try?"

In fact, you can really try.

Zheng Guo found a ditch where the water flow was not fast, and such ditch was everywhere in Wei.

The reason why the “flow is not urgent” is required because when the water flow is blocked, the flow will become more and more urgent, which may reach the level of flooding the girder.

Then, just like what Shen Bing said:

Pile piles in the ditch first, and then fill sandbags between the stakes...As the sandbags were filled in, the water flow in the ditch was blocked before long.

After the piles were filled with sandbags to reinforce them, a dike stood in front of everyone.

Zheng Guo looked at Shen Bing and exclaimed:

"Sister, this method is very good for blocking water."

"It's fast and effective. Although it consumes a lot of sacks, it's okay in an emergency."

What this says is.

No matter how important the sacks are, it won’t be more important than Mie Wei?No matter how expensive it is, it will not be more expensive than Daliang City?

And the military emergency is everything.

Not being able to use sacks in ordinary times does not mean that they cannot be used at critical moments.

Especially when other methods are not working and there is no way to go.

So Yang Duanhe no longer hesitated, and immediately ordered:

"Immediately transfer the sacks from Handan!"

"The more the better!"