20 Electromagnetism in the Middle Ages

If he wanted to create electricity, he needed to understand electromagnetics. On Earth, Faraday first discovered the phenomenon of electromagnetic induction on October 17th 1831, and then he developed a method for generating alternating current, which was regarded as an important achievement for the research of electromagnetism.

Electromagnetic induction occurred when a magnet passed through a closed circuit, generating a current.

Hence, he could maintain a closed circuit while rotating a magnet. The closed circuit would cut the magnetic induction line from the magnet in the static state. The circuit would continuously generate current, and the mechanical energy would be converted into electrical energy, thus becoming a simple generator. This theory was taught in high school physics' textbooks, and it was not considered as an advanced or difficult concept. The only problem was to acquire the basic materials and elements.

To keep this engine running continuously, it was impossible to rely on manpower. That would be inefficient and error-prone. He had to rely on natural resources, which were either wind or water. Richard had chosen to use wind power, and hence he had designed a windmill that could generate electricity, as explained in the blueprint he had given the craftsman.

However, the craftsman could only make some of the simple parts. He had to make the other parts himself, such as the complex rotors, the energy storage equipment, or the rotating shaft. This was very troublesome, and that was the reason why he would only do this as a last resort.

However, now that it had been decided, he had to carry it till the end.

First, he had to make a rotor.

The main material for the rotor was magnet. He could use a neodymium iron boron magnet, a samarium cobalt magnet, an alnico magnet, or an iron chromium cobalt magnet. However at present, there were no magnets of any kind on Blue Lion Kingdom, so he had to make one himself. He had chosen to create the simplest and most common magnet—a ferroferric oxide (Fe3O4) magnet.

To make ferroferric oxide magnets, he needed ferroferric oxide.

There were many ways to obtain this material, such as the hydrogen reduction method of α-iron oxide, the slow oxidation method of ferrous hydroxide, the Harber method, the addition method, the alkali addition method and more. In the end, he chose the addition method. The two most critical reaction substrates for this method were elemental iron (iron filings, Fe) and ferric oxide (rust powder, Fe2O3).

Taking a deep breath, Richard washed his hands, put on a dust mask to prevent powder from entering his mouth and nose, and began to work.

First, Richard put the iron filings into sulfuric acid. As soon as they were placed into the beaker, bubbles immediately appeared, and there was a violent reaction. Thus ferrous sulfate (FeSO4) was formed.

After the reaction was completed, Richard started adding caustic soda (NaOH) and ferric oxide (Fe2O3). Then he heated it up to 95-105 °C, to trigger another reaction and finally produce ferroferric oxide from the solution.

However, the ferroferric oxide was impure. Richard transferred this new solution to a funnel with filter paper and started filtering. He then dried the filtered solid matter and carried a series of procedures. After much trouble, he finally produced pure ferroferric oxide.

Through magnetization, ferroferric oxide became a real magnet and turned completely black. He repeated this step to make a sufficient number of magnets and fixed them in a ring-shaped mold. The most important part of the generator, the rotor, was created.

Yet after making the rotor, Richard did not rest, and he instead started making the energy storage equipment. Even if windmills could generate electricity, electricity had to be stored before it could be used. This required the use of real rechargeable batteries, not fruit batteries, much less capacitors like Leyden jars.

What Richard planned to make was a lead-acid battery. This was the cheapest and most common electric vehicle battery in modern times.

The reason for choosing it was that, on the one hand, the materials were easy to obtain, and on the other hand, it had a simple structure. It only had four parts: a positive plate group, a negative plate group, an electrolyte, and a container.

Except for the sulfuric acid, which functioned as the electrolyte, he only needed one, or in fact two substances.

The first substance was lead, for making the negative plate groups.

The second substance was lead monoxide, which was the oxidizing material of lead in the air. This would be for making the positive plate groups.

Many materials didn't exist in the Middle Ages, but lead was not the case. According to modern history knowledge on Earth, humans had begun extracting iron, copper, silver, and lead in large quantities at around 2000 BC.

Therefore, Richard easily acquired sufficient lead and lead monoxide.

Taking a deep breath, Richard turned serious.

Both lead and lead monoxide were toxic. Excessive inhalation and ingestion could result in heavy metal poisoning, the effects ranging from physical discomfort to death.

In Ancient Roman on Earth, the Ancient Romans had not known the dangers of lead. They had used lead pipes as water pipes for a long period of time, and they had also used lead as the material for their drinking containers. This had resulted in chronic lead poisoning for a large number of people, which had been a major factor in the decline of the Roman Empire.

Richard knew this and did not want to repeat the same mistake. He had no wish to become seriously ill even before he became a wizard, so he took adequate protection before conducting the experiment.

He first put on a dust mask before wearing another bird beak mask on the outside. He then donned a tight black protective suit that covered his entire body. Finally, he wore gloves made from cow bladder.

Once he was ready, Richard took a deep breath, feeling the air flow through the herbal sac in the beak mask into his lungs. He began working with a determined look in his eyes.

The first step involved pouring sufficient sulfuric acid into the prepared container, which would act as the strippant. Next, he inserted the gray fleece lead plate that would function as the negative electrode into the container and secured it. He then put the brown lead monoxide plate that functioned as the positive electrode inside and secured it.

He placed a separator plate between the positive and negative electrodes to prevent contact between them. After that, he repeatedly inserted a lead plate followed by a lead monoxide plate into the container, one after another, until the whole container was full.

This was so that multiple sets of positive and negative plates could form a series, thereby increasing the voltage of the lead-acid battery.

After doing this, Richard heaved a sigh of relief, knowing that the main part of the lead-acid battery was completed, and the next step was to just set up minor parts such as the external wires.

Richard continued working and finally completed it by the evening.

Bang, bang. Richard placed the newly-built lead-acid batteries and rotors on the wooden frame.

He turned around and took off his gloves, his beak mask, dust mask, and protective clothing. Only then did he realize that his whole body was drenched in perspiration.

After all, it was a hot summer day. Even if he was in the relatively cool palace, it was still a torture to work the entire afternoon. He had not noticed it when working. However after completing the work, he had felt his underwear clinging to his skin, his whole body sticky.

Frowning, Richard opened the door and walked out of his private laboratory.