In order to cooperate with the propaganda plan, Beihai began to build brick-burning earthen kilns on a large scale. These brick kilns are tall vertical kilns, and the fuel used is not firewood and grass, but briquettes characteristic of Beihai country.

These spherical briquettes made of pulverized coal may not be as efficient as honeycomb coal. However, in large-scale production, it is much better than honeycomb coal. Because the load-bearing capacity of honeycomb coal is poor, and the requirements for placement are high, it needs to be eye-catching, which is very inconvenient for production. Therefore, large furnaces and earthen kilns prefer briquettes as a simple and crude fuel.

The problem with briquettes, though, is that they burn too hotly......

If you use firewood and grass kilns, the temperature is generally not very high, and it usually reaches 700 to 1000 degrees Celsius. And it just so happens that the temperature range of burning bricks is between 900 and 1100 degrees. If this temperature is exceeded, what is burned is the burnt brick (also called the burnt brick), and all kinds of deformation are irregular.

The temperature of the earthen kiln with firewood and grass generally does not exceed 1100 degrees, but the temperature is not enough. This is not the case with coal, which is particularly easy to burn......

You must know that coal can be burned to the level of 1700 degrees or even 1900 degrees when the blast is sufficient. Therefore, using briquettes to burn bricks and controlling the temperature has become a big problem.

Later, Marin came up with a way to measure the temperature with copper wire......

Marin remembers that the melting point of copper was 1,083 degrees, which was very close to the upper limit of 1,100 degrees for burning bricks. So, he came up with a way to have someone use a clamp to hold a small piece of copper wire and poke it into the furnace. If the copper wire melts, it is overheating. It does not melt, it is natural and normal......

Of course, this is only for pre-testing. If you use a copper wire to measure the temperature every time, you will lose a lot of copper. In the beginning, the use of coal to burn bricks was a variety of conditions, and there were a lot of strange over-fire bricks. Later, after losing a lot of copper wire, some craftsmen who were good at burning bricks renovated the road and added some vents to avoid the kiln temperature being too high, and finally controlled the temperature.

Then, Marin asked people to compile a work manual, take the test and mature briquette vertical kiln as a standard, and began to promote it, so that people can work according to the standard guidance steps. Sure enough, a lot of low-cost bricks were easily fired.

You know, coal has a low cost and high combustion heat, which is much more convenient than using firewood and grass. In order to publicize it, Marin also built several briquette brick kilns near Port Emden, burning bricks for outsiders to see all day long. Although he polluted the atmosphere, Marin didn't live in Emden, so what about him......

As truckloads of bricks were pulled out of the briquette kilns near Port Emden and shipped out to sea (supposedly destined for the Americas), people saw that it was believing, and they had to believe it......

In fact, the brick kilns in Port Emden are only exemplary. The real bulk of the production is still on Cape Breton Island.

The local area is close to the Sydney coal mine, and the soil resources are abundant, so it is not too easy to burn bricks. If a large number of bricks are burned in Beihai Country, Marin is reluctant to have soil resources. After all, the native land resources are not so abundant, and the clay is also very precious, right?

But the Americas are different, the most important thing there is is the land and soil, and you don't feel distressed to burn bricks casually. Moreover, although the Sydney coal mine on Cape Breton Island does not produce a lot of coal, it uses less coal in this era when there is no industry. Just right, using coal to burn bricks is also considered to make the best use of things and avoid waste.

Marin calculated that if briquettes are used to burn bricks, the cost of briquettes is much lower than that of firewood and grass. In addition, the calorific value of briquettes is high, which can burn more bricks and expand the kiln body a lot...... As a result, more bricks can be burned and the cost is much lower...... In the end, the cost of bricks burned in the briquette kiln is several times lower than that of the firewood kiln......

Moreover, coal gangue and cinder can also be crushed, mixed into bricks, fired bricks, and saved soil......

Marlin calculated and calculated, and finally discovered a secret - that is, although bricks are expensive, they are also made by people. In fact, the cost is mainly consumed in manpower.

For example, a brick kiln was set up near the coal mine on Cape Breton Island, and the fuel coal was produced by Marin's own coal mine, which only required labor costs. The same is true for firing bricks, whether it is to make bricks, or to fire kilns, and to ship bricks later...... In fact, the cost of materials is almost negligible. The real cost of bricks is still generated from human labor.

In other words, as long as there are enough people to burn bricks in a place like Cape Breton where coal and earth resources are abundant, you can burn a lot of cheap bricks at the cost of manpower. Even if it is shipped back to the mainland, it is less expensive than burning bricks in the country. After all, not to mention the clay cost of burning bricks locally, and the briquettes have to be transported from as far away as the Ruhr or Newcastle.

And this kind of low-cost bricks is very conducive to urban construction. Previously, in order to save money, Marin promoted low-cost adobe houses in the country. But this kind of house is okay in the countryside, but in the city, it doesn't seem to be harmonious. Therefore, Marin's plan is to gradually replace all adobe houses with brick houses in the future.

At that time, in the cities of Beihai Kingdom, this kind of low-cost sintered brick tile house will be popular. In addition, cement is used as a binder between the bricks. After the masonry is completed, the outside of the house will be plastered with cement, just like the kind of square that was popular in the Chinese countryside in later generations. Then, brush a layer of lime on the outside of the cement, which is white, very eye-catching, and beautiful......

Although the cost has increased significantly, Marin knows that this will also boost GDP. Besides, the brick-burning business is also Marin's own. Even if you earn less, you can still make money. In short, it can be regarded as stimulating domestic demand. This is the trick of China's economic construction in the 21st century - infrastructure madness and stimulating domestic demand......

In order to make a name for himself in France, the brick ship sent by Marin deliberately docked and replenished at the port of Le Havre at the mouth of the Seine River in France, so that the French saw with their own eyes that many bricks were pulled to the Americas to "build the Great Wall". The news would then travel down the Seine back to Paris......

In fact, the port of Le Havre was historically an important port that was only built by order of François I in 1517. Today, Le Havre is just a small fishing village port.

But Marin knew the potential of this port, and had already arranged for merchants from the Beihai Chamber of Commerce to infiltrate the area, buy a large piece of land, and build a wharf to make it an important port of berth. By the time François I began to build here, the merchants sent by Marin before would be able to drink the soup and get a lot of benefits.

Because of the presence of Marin's merchants, Le Havre, a small fishing village, has gradually formed a port town, but the walls have not yet been built.

Marin's merchants built several long-bridge docks, warehouses for rent, and taverns and inns. In time, even if François I did not order the reopening of the port, it could have developed. Because, the conditions here are so good - located at the mouth of the Seine, it can be connected to the capital Paris, and it is definitely a first-class transshipment port......

The brick-carrying ships of the North Sea Kingdom deliberately docked here for supplies, and the sailors were also instructed to go ashore to the tavern to drink and brag. I believe that it will not be long before the news reaches Paris. In this way, it will be convenient for Marin to send people to recruit immigrants......