That's right, Zhang San thought of bird manure, legend has it that bird manure is rich in nitrogen, phosphorus and potassium, and it is definitely an artifact for increasing grain production, and it is definitely not difficult to find bird island on the sea, as long as you get good fertilizer, it will be of great significance to Zhang San.

Not to mention that doubling the yield per mu is increasing the yield by half, that is equivalent to a person who can grow two people's rations to growing three, which is definitely equivalent to doubling the population.

Of course, the amount of manure produced by a small island may not be very much, but Zhang San does not need much, as long as the output increases in the first few years, and it is carried over, and after more people, the land is developed and perfected, and there is enough to grow without fertilizer.

Thinking of this, Zhang San immediately arranged for people to find Bird Island, and whether there are any places like bird gathering places on Ryukyu Island, or even bat droppings in the bat cave.

After seeing the cannery, Zhang San went to the oil refinery next to him, although Zhang San had asked the whaling ship to pretreat the whales, but this large-scale boiling oil still has some strange smell, but it is not very smelly.

Animal carcasses are easy to stink, but processed pork and beef can indeed be preserved for a longer time, because there are many organs in the animal carcass, especially in the intestines, there are a large number of bacteria, and the accelerated reproduction of bacteria causes the internal organs to decay rapidly, and then the corpse quickly decays.

After the pretreatment, although the rotting of the meat was slowed down, the whale's fat was used to boil the oil, so it was not salted, so after a few days, there was still a copy that quickly deteriorated.

Zhang San pinched his nose and turned around, and came to the refined oil depot area, where a large vat of whale oil was placed there, Zhang San asked people to take a little as lamp oil to try, and sure enough, it was bright and less fume.

Zhang San nodded with satisfaction, and immediately ordered the carpenter workshop to speed up the production of wooden barrels, but because the carpenter workshop had too much work to do, it was impossible to allocate too many people to make wooden barrels.

However, before the wooden barrel was not made, Zhang San thought of the mountain of bamboo he saw by chance, and Zhang San planned to make a bamboo tube to save manpower, so that a bamboo tube was loaded with half a catty or a catty, but it was easier to sell.

It is very common to do it when you think of it, so even if you are on the beach, you can find a large bamboo forest, and then you need some saws, drilling tools, and a cork.

This bare bamboo is not good to hold the handle of weaving a hemp rope, and then thinking about it, I still feel that something is missing, Zhang Sanyi patted his head trademark, and he actually forgot this.

The lettering on the bamboo is too laborious, and the bamboo is afraid of cracking it with fire, Zhang San thought for a while, anyway, this thing is going to be sold to Yixing Hutchison, and simply using the anti-counterfeiting trademark of Yixing Hutchison is the trouble of the province.

In addition to being used to make lamp oil, whale oil can also be used to make soap, but Zhang San thought that it was too wasteful to use such a good oil to make soap, so he would just get a batch of whale oil and sell it as lamp oil.

As for the tea oil, Zhang San has begun to buy a large number of tea fruits in the mountains near Hangzhou and Fujian, and then use tea oil to make soap, and the first batch to use the whale oil lamp is Zhang San's own Yixue, after Zhang San moved the Yixue on Sea Shark Island to the Ryukyus, the conditions are slightly better than before.

In just three months, there is only enough time to build a batch of wooden classrooms, and the foundation of the new brick classrooms is still being laid. Although Zhang San wants to list the bricks used in Yixue as the first batch of bricks, there are too many places that need to use bricks now, and too many people cannot be arranged to do this, so the brick kiln is still mainly producing road bricks.

Only a small number of ordinary bricks are used in some key places, so Yixue can only use wood to make do with it first, anyway, this southern winter is not cold, and Zhang San is not afraid that the children will be sad in winter.

It's just that the children's enthusiasm for learning knowledge is very high, and there are some skilled workers who don't have time to train during the day, so Zhang San approved the school to give priority to the supply after the first batch of whale oil was boiled out.

Now that the whaling ship has found out its experience and entered a stable harvest period, Zhang San thought about it and waved his hand to supply whale oil to Ryukyu Island at the price of ordinary lamp oil, which will greatly enrich the nightlife of the islanders.

After seeing the whale oil refining factory, Zhang San went to the salt factory again, the production of sea salt is in an orderly manner, and the workers have accumulated a certain amount of experience after several months of exploration.

Zhang San once tried the so-called process of making refined salt, and confidently thought that after filtering a few more times, the coarse salt would become refined salt and then the price would increase many times, but after the actual operation, Zhang San knew that this thing was a pit.

Sea salt is bitter because it contains a lot of impurities, but these impurities are soluble in water, which means how bitter or bitter the sea salt should be after you filter and distill it a hundred times.

Therefore, this method of making refined salt will definitely not work, Zhang San knows a physical method, that is, the use of different substances and different crystallization conditions to filter substances other than sodium chloride in sea salt, but this kind of high-tech has not yet been mastered by Zhang San.

One of the friends is to use chemical methods to make other chlorides in sea salt react into precipitated substances, but unfortunately that kind of substance can be used to achieve such an effect, Zhang San didn't know at all.

Therefore, compared to the chemical method, Zhang San felt that it was easier to study the method in the house, so Zhang San arranged for the salt field to try to make refined salt, handed them the method and promised a heavy reward.

It's just that it turns out that Zhang San really thinks too much, the master who manages the salt farm has been trying hard for several months, but the harvest is really not much, Zhang San is not in a hurry, it is good to get it, if you can't get it, there is no way, anyway, ordinary salt is also a lot of money.

This time, after Zhang San began to lay a large-scale network of influence on Fujian Road, the sale of illicit salt is no longer a problem, so the first batch of illicit salt will be shipped to Fujian within half a month at the latest, and the smuggled salt dealers will sell it to the mountainous areas of Fujian and Jiangxi.

For this illegal salt sale, Zhang San also planned to organize a raid on several private salt farms in the Fujian Road area, and these salt cooking factories had a lot of workers, and Zhang San did not have to play the role of a pirate.

Therefore, robbing these private salt farms can not only grab a large number of laborers, but the owners of these private salt farms have a bit of family background, and then it will definitely be a talent and a win, and there is also a little bit of benefit in robbing them.

That is, the government will not take care of it, and many salt factory owners may not report to the officials and plunder the population along the coast, not because they can't do it, but they can't do it on a large scale, otherwise they will make a lot of noise and may lose more than they gain.

However, once there are casualties, it may be reported as a massacre, which is extremely unfavorable for Zhang San's next recruitment, so it is Zhang San's goal to rob these illegal salt farms and some fishing villages that are half fishing and half pirates.