My physics masters couldn't possibly be grand mages.

Einstein seemed to realize something, "You mean...."

"Alchemy," Char said.

"What is that?" Tesla asked curiously. "Can it really refine gold?"

"We had an alchemy class yesterday," Xia said. "The teacher said that some high-level alchemists are able to refine gold."

Tesla opened his eyes. Clearly, for someone living in a scientific world, the magic of this concept had a certain impact on him.

Of course, science is a methodology, and in a sense, this also belongs to "science," it's just that they haven't yet understood its principles.

"To transform one element into another, the number of protons in the atomic nucleus must be changed," Tesla murmured.

Einstein looked at him, and the corner of his mouth twitched slightly.

"Rutherford did it in 1919," he said. "Nitrogen turned into oxygen."

"That's bombardment," Tesla said, his gaze still fixed on the target. "Bombardment with alpha particles. Extremely inefficient and extremely costly."

He paused, then continued, "So... do you know alchemy?"

Einstein shook his head. "The first lesson was just some general knowledge of alchemy."

"To use alchemy anytime, anywhere, you need five runes," Char said. "The spell you just used to shape the lightning was one of them. It requires the elements of 'Understanding,' 'Deconstruction,' and 'Reconstruction' from alchemy."

"According to the working logic of alchemy, it should theoretically be able to directly decompose hydrogen and oxygen from water. This is different from the logic of converting magic into electricity and then using electrolysis of water to produce hydrogen and oxygen, which results in a significant loss of energy during the conversion process."

He paused, then said helplessly, "But of the three of us, only Mr. Einstein has a chance of learning it, and even that is just a chance. The transmutation array is a configuration that can only be learned by fourth-order cultivators."

"Anything else?"

"Then we'll have to use the Alchemy Disc," Xia said. "It needs to be rented; if we buy it outright... we'll need points."

He scratched his head and didn't say anything.

Tesla noticed the embarrassment on his face. "So hard to get?"

"A loan costs 10 points per day, while a buyout costs 600 points. To buy out, you'd have to work for six months without eating or drinking."

The courtyard was quiet for a while.

"We don't need that much hydrogen right now," Einstein said. "We can start a second project to maximize the use of hydrogen's chemical energy and generate even greater power."

"Gas manipulation," Tesla murmured. "If we can gather hydrogen, and separate oxygen from the air, can we compress it?"

Char thought for a moment. "Theoretically, it's possible. Compression just forces gas into a smaller space, but I haven't tried it."

"Let's try it now," Tesla said.

He looked at Einstein, "You make it."

Einstein is the most magical person here, so it's the most suitable place to produce large quantities of hydrogen.

He moved the chair to the edge of the pool, sat down, and gently lowered his left hand.

With a crackling sound, electricity surged into the copper wire, and the bubbles in the pool began to rise again.

Tesla raised his hand and used "gas manipulation" to mix the separated hydrogen and oxygen in a simple way.

It was about the size of two or three balloons, suspended in the air, invisible to the naked eye, but Char could sense it with his mental power.

"Press it into a ball," Tesla said. "The smaller the better."

Char closed his eyes and activated the gas manipulation rune.

He first sensed the boundary of the mixed gas.

It is loose, like a clump of cotton wool, with large gaps between gas molecules.

He began to apply pressure to the center from all sides, using magic to push the gas molecules inward.

The gas began to contract, gradually shrinking to the size of a balloon.

Char's forehead began to sweat.

He felt the pressure pushing his magic in the opposite direction.

The more tightly a gas is compressed, the greater the repulsive force between its molecules.

"Can it get any smaller?" Tesla asked.

"...I'll give it a try."

Char gritted his teeth and increased his magical output.

The balloon gradually grew to the size of a grapefruit—about fifteen centimeters in diameter, with a slightly shimmering surface and the internal flow clearly visible.

His fingers began to tremble slightly. Not from nervousness, but from his mental energy being depleted too quickly.

Compressing the gas was much more difficult than he had imagined.

"That's about it," Einstein suddenly said.

Char opened his eyes and let out a long breath.

A transparent, slightly glowing sphere, about the size of a grapefruit, floated above his palm.

Einstein stood up from his chair, walked over, and used gas manipulation to take the compressed hydrogen-oxygen mixture sphere from Char's hand, continuously inputting magic power to maintain its shape.

"The pressure... is about nineteen to twenty atmospheres," he said. "That's equivalent to the pressure at a depth of 200 meters. It's dangerous, but controllable."

Tesla reached out, brought his face close to the small ball, and squinted at it.

"Detonate it," he said.

"Here?" Xia looked around.

"Go outside." Tesla tilted his head toward the open space outside the yard. "A compressed hydrogen-oxygen mixture of this size has an explosion radius of about three to four meters."

The three men walked out onto the grass outside the yard. Einstein held up the sphere, which was about the size of a grapefruit.

He didn't rush to put the sphere down, because once the compressed hydrogen-oxygen sphere was out of magical control, the high-pressure gas inside would violently expand and disperse within milliseconds, not only losing its power but also potentially causing unexpected dangers due to disordered diffusion. Therefore, he needed to find a way to maintain its compressed state.

He knew what was suitable: the rune Tesla had previously used to control the current and prevent himself from getting electrocuted.

"Form endowment" and "stability".

Stability means maintaining a certain form of matter or energy for a period of time.

He raised his hand and imbued the compressed hydrogen-oxygen ball with "stability," then placed it on the grass.

He stood up, took a few steps back, and raised his right hand.

He activated the energy release rune. A small flame appeared in his hand, which he attempted to throw at the hydrogen-oxygen sphere.

However, due to the great distance, the flame landed about five or six meters to one side of the sphere, making it extremely difficult to hit.

Tesla couldn't stand it any longer. He moved a little closer, used his magic to create flames, and threw them at the attacker.

The moment the flame left his hand, he had already turned and run two steps—his movements were faster than those of an 82-year-old.

At the same time, the flames struck the sphere—

"boom!"

A short, sharp bang made Einstein and Tesla's eardrums ache slightly.

A blue-white fireball exploded at the location of the sphere, with a diameter of more than two meters, and lasted for less than half a second.

The heatwave spread outwards from the sphere, pressing the grass flat against the ground, with the grass blades closest to the explosion point turning yellow and curling.

A shallow pit, about the size of a plate, was left on the ground. The soil at the bottom of the pit was burned black and was emitting blue smoke.

The shockwave swept across the three people's faces, hot and burning, with a burnt smell.

The three were silent for a moment. Then Tesla crouched down and touched the edge of the shallow pit.

"...It's feasible," he said.