The water had been boiling and cooking the beetroots for some time now, its steam escaping through the makeshift chimney into the dark sky.
Seeing the beetroots essentially cooked, Alexander took the heavy, hot pot off the stove and slowly emptied the contents through a cloth strainer into another large pot.
Then Cambyses cleaned the strainer and helped Alexander repeat the process multiple times, switching the sweet water multiple times between the two pots, to try and filter out as much of the scum and debris as possible.
Normally, it would be at this point that they drank the water.
But today, Alexander decided to process the water even more.
He took out some of the limestones from his pouch and holding the crushed powder by his fist, he put all of it into the hot sweet water.
He then quickly placed the pot again on the stove and started vigorously stirring it with a large wooden spoon.
This move surprised Cambyses, but she did not react too strongly.
After all, she had seen Alexander do plenty of strange things before, and it usually produced something amazing.
So she patiently waited by his side, holding a large candle to better illuminate his surrounding.
What Alexander was doing was basic high school chemistry.
For him to get the people to drink the bitter poison he had prepared, he needed to first refine the sweet water more and increase its sugariness to hide the bitterness.
To do that Alexander asked the question 'Why does my sweetwater taste bitter and sour? And not sweet like juice?'
And he came up with two different reasons.
He reasoned that most of the bitterness was due to improper cleaning and from the unfiltered micro-fibres.
So to reduce the bitterness, he decided to thoroughly clean the beetroots beforehand.
Also, he used a cloth strainer multiple times to slowly filter out much of the micro-fibres.
Usually, like how the sweet water was being prepared in the medical camp, they used a large strainer with wooded holes to just catch the large beetroot pieces. and let all the small fibers into the drink.
But he hoped that the cloth will capture everything and only filter the water.
In this way, he hoped that these two additional steps would reduce the drink's inherent bitterness.
As for the presence of sourness, Alexander reasoned that most likely it came from the organic acids present, as he remembered acids being sour.
So he decided to use an acid-base reaction to neutralize it.
Limestones also known as Calcium Carbonate was available to him and he knew that he could use it to make lime water, chemically called calcium hydroxide, which was a base, and make it react with the present acids.
To make this, he would need to decompose, under heat, the insoluble and nonreactive with organic acids, calcium carbonate into calcium oxide, and carbon dioxide.
The carbon dioxide would bubble away as gas and the calcium oxide would then react with the hot water to make the base calcium hydroxide.
This base would react with the acids to make salt and water, thus neutralizing the sour taste.
That was the theory anyway and when Alexander put the limestone powder into the sweet water, he intended to put his high school chemistry knowledge to the test.
The reaction soon started taking place, characterized by the bubbles of carbon dioxide coming out of the water, which drew an astonished gaze from Cambyses, and after some time the bubbles died down, signaling the decomposition reaction was over.
Understanding this, Alexader stirred the pot for a while longer letting the base and acid have enough time to react, and then, finally after some time, took the pot off the stove and filtered the water one last time.
Two pair of curious eyes soon cast their gazes on the new product and from the color alone Alexander could tell it was a success!
Alexander's theory had been proved right and even under the poor candlelight, Cambyses could see a marked difference between this sweetwater and what she usually had.
It was much clearer.
Alexander then gestured for the girl to have a taste, and so without further ado, she took a small spoonful, blew on it to cool it down, and sipped it down.
"Honey! It tastes like honey!" She screamed in joy, thinking she was drinking pure honey.
Cambyses had only ever once managed to taste a bit of the crazy expensive liquid called honey and this taste reminded her exactly of that.
And felt ecstatic while drinking this, both because of the taste and because she knew that from now on she could drink such a delicious product from such a common product as beetroot.
"It tastes passable." Alexander, on the other hand, from the side unfeelingly commented.
To him, it was, though a lot lesser, still a bit bitter and sour. And now it tasted a bit salty from the newly created salts. It was a far cry from the store-bought white granular sugar he usually bought, but he figured that the sweetness had increased just enough to be able to hide the poison's bitterness.
"Passable? You mean you tasted something sweeter?" Cambyses asked with incredulity.
But only received Alexander's enigmatic smile.
Alexander then nonchalantly put his hands inside the pouch and bought a few sleepknot leaves Mean had given him, rolled them into a ball, and squeezed them, dropping a few drops of the leaves' juices into the sweetwater.
"*Gasp*" Came Cambyses's huge gasp as she looked at Alexander in disbelief.
She had finally figured it out,
She had been asking herself how could Alexander possibly poison those men, who were quite likely on high alert.
And only now she understood it.
The sleepknot leaves juices he used were regularly administered in small quantities as sleeping medicines.
This property had been known for thousands of years and the lethal effect of taking it in large doses causing a heart attack in sleep was also well understood.
So, it would be impossible for Alexander to make anyone drink a bitter drink.
'This was why he made a sweeter drink, to camouflage the poison' A light bulb went off inside Cambyses's head.
But this was only half of his genius.