Sending away Shi Weila, Zhu Cijiong suddenly remembered the problem of iron ore transportation, it was good to say at sea, there was Shi Weila's own merchant ship to send it, but after arriving at the port of Tianjin Wei, it had to be transferred to the capital by horse-drawn carriage.

The distance from the capital to the port of Tianjin Wei is not far, about two hundred and fifty miles, and it can be reached in more than three hours, but the problem is that the carriage can not pull the goods quickly, and can only walk slowly, so it takes at least two days for the carriage to rush from Tianjin to the capital, counting the time of loading and unloading, it is almost three days.

And like the dirt road of the Ming Dynasty, a carriage can pull about 1,000 catties at most, and if there is more, the road will be crushed, not to mention, the wheels of the carriage will often sink into the dirt pit, and they can't pull it out.

In this way, it takes 2,000 horse-drawn carts to pull 2,000 pounds of iron ore for three days, and if it is made into weapons and then sent to Liaodong by water, it will take almost 2,000 horse-drawn carriages for three days, as well as the grain, grass, baggage, and silver of 400,000 troops.

This is only the transportation of military materials, if the economy develops, the volume of goods transported is called a terror, I am afraid of tens of thousands of people, tens of thousands of carriages to and fro non-stop, in that case, people eat horses and chew plus silver and loss, a month alone transportation will cost 100,000 taels!

What to do? In fact, it is very simple, that is, to develop a steam-powered train, in that case, to make a few locomotives, each pull a few freight cars, as long as a dozen people to drive the train, it can completely top the transportation of tens of thousands of horses. And after the steam train technology matures, it can also engage in passenger transport, at that time it will be much more convenient for ordinary people to travel between Beijing and Tianjin, the so-called want to get rich first to build roads, the flow of people and logistics is convenient, the economy will slowly be revitalized, it can be said that nothing can stimulate local economic development more than road construction.

In fact, with the development of steam power application technology in the Ming Dynasty, it has long been possible to build a steam-powered train, and the reason why Zhu Cijiong did not think about building a train in the past is mainly a matter of cost.

Not to mention the cost of the train, just talking about this railway, you must know that the weight of a meter of standard track is more than 100 catties, and a row of two-way round-trip railways is four tracks, just take the distance between Beijing and Tianjin Wei, 250 miles is more than 120,000 meters, a row of four one meter is more than 500 catties, more than 120,000 meters is more than 600,000 catties, and it is 1.3 million catties of iron ore when converted into iron ore! Coupled with the sleepers and the labor to build the railway, this section of the railway alone will take several months plus hundreds of thousands of taels of silver!

In the past, there was no such large transportation volume, which was tantamount to wasting money, but now it is different, with such a large transportation volume, it is not only not a waste of money, but a saving of money.

Now that the conditions have been met, let's start 'research and development', to say that this steam-powered train Zhu Cijiong has really not seen the real thing, the steam-powered train in his previous life has long been eliminated, the worst are diesel locomotives, the general high-speed trains are electric locomotives, but fortunately, many books that introduce the history of scientific and technological development have mentioned steam-powered locomotives, and he has also seen a few articles introducing them, this steam-powered locomotive is not very complicated, and he tried to recall it and remember the general structure.

The steam-powered locomotive is mainly composed of boilers, steam engines, frame running parts and coal water trucks, the boiler is needless to say, the main thing is to use coal to boil water into steam, this is now very mature, there are many boilers in Wang Gong factory, from the initial simplest thing like a kettle, has been improved into a new type of boiler with safety valves, simple water level gauges, simple steam pressure gauges and other auxiliary devices, and modern boilers are basically the same, completely enough for steam power trains.

The steam engine is actually a set of things that use a piston to drive the wheels to rotate, so as to push the locomotive to run, which is similar to the cylinder, piston and transmission device used in the machine tool, but it is a little bigger, with Song Yingxing's technology, this is no problem at all.

The running parts of the frame are not very complicated, mainly the pushing wheels and the front and rear steering wheels plus the spring shock absorber and the traction device of the rear wagon, which is not complicated for people who have seen trains, but it is a little difficult for people who have never seen trains to imagine out of thin air.

The last coal water truck is even simpler, that is, it is loaded with coal and water and some other spare parts, and there is no technical content at all.

In general, the only difficulty in 'developing' a steam-powered train now lies in the frame walking parts, because Song Yingxing and they have never seen a ready-made train, and there is no intuitive concept, so it is more difficult to imagine it out of thin air. Of course, if Zhu Cijiong is asked to do it, this problem does not exist, but he is now the emperor, how can he do that 'rough work', so the main problem now is to guide Song Yingxing and them to make the frame walking parts, and the other three parts can be said to be ready-made, and they can be superimposed when the time comes.

How to guide it? Zhu Cijiong racked his brains and finally remembered a simple thing, that is, a flatbed rail car used to transfer parts inside a general mechanical assembly workshop. This thing is really simple, it can't be simpler, it's four iron wheels, and a big plate on it. But this thing is similar to a train, because this kind of flatbed car is also stuck on the iron track, of course, this rail is not a real train track, but two square steel or angle steel buried in the ground.

Don't look at the simplicity of this flatbed rail car, if you add a few push wheels in the middle, it will look similar to the bottom of the train!

Thinking of this, Zhu Cijiong no longer hesitated, and directly summoned Song Yingxing over.

Song Yingxing thought that there was some major project, but Zhu Cijiong just smiled when he saw him and asked: "Chang Gung, it's very troublesome to move the barrel from one machine tool to another or from one workshop to another in the workshop." ”

He was stunned when he heard this, isn't it troublesome, hundreds of thousands of pounds of things, although they can be hoisted onto the trolley, but it is called a lot of effort to push it, one or two people can't push it at all, and three or four people must go on it together. However, this is just a trivial matter, why did the emperor suddenly care about this?

He replied cautiously: "Back to the emperor, it's indeed a bit troublesome, it's too heavy, if you push it alone, you can't even lift the handle of the trolley, you have to carry it by two people, and you have to push it by one or two people." ”

Zhu Cijiong nodded and said, "Well, I have thought of a solution for you, you can take a look." ”

As he spoke, he took out a blank piece of paper and drew a sketch on it, which was a flat plate with four wheels. Then he explained: "This is a flatbed, the wheels are iron, if you pull a single barrel, you can make it smaller, and then put a half-man-high handle on it, just pull it and walk without lifting it." If you pull a bunch of gun barrels, you can make it bigger, but the slate ground is estimated to not be able to bear such a large weight, so you have to bury two square iron bars in the ground, and then the inner surface of this wheel protrudes a little bit to prevent the flat wheel from detaching from the iron bar, understand? ”

Song Yingxing looked at it carefully, nodded and said: "Weichen understands, but please forgive Weichen for being stupid, how thick should this plate be, iron plate or wooden board, and how thick is this iron bar?" ”

Zhu Cijiong probably thought about it for a while, and replied: "Just use a two-inch thick plank, you won't pile hundreds of thousands of catties of things on it, as for this iron bar, tens of thousands of catties of things are enough to use two inches of square iron bars." ”

Song Yingxing was a little eager to try: "I don't know if the emperor has anything else, if there is no Weichen, I will do it now." ”

Zhu Cijiong waved his hand and said, "Go ahead, it's done, give it a try and tell me how it works." ”

Song Yingxing immediately retired in a hurry, in fact, he also thought about this problem, but in ancient times, there were few wheels made of pure iron, so his direction was wrong at the beginning, and he had also done four-wheeled vehicles, and it was indeed not very difficult to push, but the size and load-bearing capacity of the wheels determined that the four-wheeled vehicles were not suitable for use in the workshop. You must know that the ancient wooden wheels were almost all large wheels with a diameter of more than one meter, and the four-wheeled car was at least three meters long and more than one meter wide, and it could only transport one or two cannon barrels, and it was impossible to bear it with more wheels. He now casts a batch of 100 cannon barrels, so at least fifty of these big cars must be made in the workshop, in that case, the aisle will be basically blocked, which will affect the efficiency, so he will give up after trying, and it will be better than blocking the workshop.

This time it's different, according to the emperor's words, push one or two cannon barrels of the trolley to make four palm-sized iron wheels, so that a meter long is just enough to put down the cannon barrel, even if it is fifty can't occupy much space, as for the large rail flat car, it seems that according to the emperor, it is okay to put forty or fifty cannon barrels at a time, but I don't know if it will be pushed or not.

Song Yingxing was originally interested in these things that would help improve productivity, otherwise he wouldn't have made up any "Heavenly Creations", so after the emperor proposed this plan, he couldn't wait to go back and experiment with it.

Wheels and square iron these things are very simple, cast a rough shape, and then go to the car a few knives, milling a few knives are basically formed, two-inch thick planks are not difficult to find, bearings are also ready-made, so the next day he will be all ready, assembly is a bit troublesome, after all, the first time to do, there will always be a little problem in the connection of the parts. But this is not difficult for him, who told him that there are many beds and many people, so on the third day, he made a small flatbed car and a rail flatbed.

He first tried a small flat car, a thousand pounds of 417 howitzer barrel pulled up by one person is not very difficult, two is more difficult to pull alone, but the pull is still barely pulled, the kind of cart with four wooden wheels is different, a cannon tube is barely pulled by one person, two barrels must be two people, in these two aspects the four iron wheels of the trolley are completely victorious, coupled with his small size, Song Yingxing decided, this kind of small cart, all workshops are equipped.