CHAPTER 9 #2
In her past life, she had watched her own children grow from youth into old age, with the eldest son’s hair turning gray just like hers.
Wherever they were now, she didn’t know, nor whether they were happy.
“How did you do that?” a child beside her asked. “Was that magic?”
Hedy snapped out of her thoughts and asked Dechio to bring over her newly published Maternal and Child Encyclopedia. She flipped through it for a moment and found the “Heimlich Maneuver” section.
Lorenzo, confirming that his son was back to normal, took the book and glanced at it.
There were clear instructions on how to perform the procedure, and it was exactly the same as what she had just done.
Not only that, there were also emergency procedures for different age groups and choking conditions, along with detailed explanations.
“You did very well,” Lorenzo said, looking at her. “And you saved both of my children.”
“What do you want as a reward?”
Clarice had also regained her composure, her face filled with gratitude.
“Please, let us repay you—Piero is my beloved, and he almost lost his life just now!”
Hedy was momentarily stunned, then suddenly spoke up, “If one day I wish to travel to other city-states, could you offer me some support?”
She wasn’t sure when she would leave, but it was a possibility after all. Wealth and power might bring misfortune, but providing some convenience to travelers should be harmless.
“If that day really comes, we will write you a letter of recommendation and arrange for better places to stay,” Clarice said, taking her hands in hers, breathing deeply. “You will always be a guest of the Medici family.”
Lorenzo looked at her, quietly nodding in agreement.
Soon, new guests arrived at the palace, but they weren’t seeking the lord. Instead, they came to consult the alchemist.
Since Hedy had gradually become famous due to her discoveries in microbiology and her various papers, especially as a distant relative of the Medici family, she had to ask a maid to help handle the increasing number of letters and love gifts she received.
The gifts were all politely refused, and the letters were selectively answered.
Some of the questions were quite bizarre but did reflect the characteristics of the era.
There were people asking if she had ever seen God or the Virgin Mary, whether the dead could come back to life, or if there was a way to reach heaven ahead of time.
Others asked her to cure their bedridden, dying mothers or inquired about the details of the operations described in her Maternal and Child Encyclopedia.
Hedy knew that every action she took had likely already been scrutinized, and any letter containing inappropriate content would be promptly reported to the lord. She had never made a mistake in her work.
Today’s visitor was a man referred to as Duke Enzo, who was said to be a prominent figure of some repute.
Upon his arrival, even the lord accompanied him for tea, clearly showing a great deal of respect.
Hedy was called over and performed a greeting before listening in on their conversation.
The discussion, however, went from the weather to business, then back again, so dull that it almost made her fall asleep.
After about thirty or forty minutes of pleasantries, the elderly gentleman hesitated before finally revealing his true reason for visiting.
“You know, how can one confirm if a child is truly theirs?”
The question sounded both humiliating and complicated, clearly hiding some deeper story.
Hedy snapped back to attention, shaking off her drowsiness and began listening closely as he shared some of his past secrets.
Duke Enzo was over fifty years old and had four wives in total. His new wife was only in her twenties, still in the bloom of youth.
The issue was that their child, despite inheriting both hair and eye color from his parents, always seemed somewhat unwell.
Hedy began to sense something here. It was no wonder that they had asked Mr. Medici to come listen in on this matter—it seemed like a precautionary measure against her.
"So..." the old duke nervously rubbed his hands, "Is there anything that can be done?"
"Hmm..." She turned her gaze toward Medici, silently seeking his opinion.
Some tasks, even if they are simple to do, might not be worth helping with. Helping could bring more trouble than a mere thank you.
The duke seemed to sense her unspoken question and subtly nodded.
Building a relationship with Duke Enzo would be very beneficial for developing the banking industry in the south.
In a split second, Hedy confirmed the information with Medici, then nodded toward the elderly gentleman.
"It should be possible," she said, pausing before adding cautiously, "It will likely take about half a month, and I may need some things, such as blood—but I assure you, it will not be used for any form of witchcraft. The specific methods will be explained to you later."
When the old duke heard that there was hope, he visibly relaxed, nodding eagerly. "A child is the father's flesh and blood, so of course, it requires blood—there's no need to be so tense!"
Lorenzo gestured for her to step back, then smiled as he engaged the duke in further conversation, discussing rumors from the south. They talked for quite a while.
Although Hedy wasn’t a doctor, she was well aware of her own blood type and some related stories.
She was well-connected and had been married to husbands from different professions, through which she had met people from various circles.
Because of this, she once heard a fascinating story from a scientist.
In this world, there are generally four main blood types: A, B, O, and AB.
These four blood types symbolize many things.
Type O blood is believed to be the earliest dominant blood type in history, often called the "hunter blood type." People with this blood type lived on a high-protein diet and were in the primitive stage of human history.
As agriculture developed, many people began to rely on farming, gradually evolving a digestive system better suited for grains, with lower stomach acid. These were the first immigrants and farmers, the pioneers of new history.
Type B blood is common in the Eurasian steppes, carrying the characteristics of nomadic people and also having antibodies that counteract Type A blood.
As for Type AB blood... Hedy had heard from her friend that it represented modern times. It was a blood type that emerged gradually as various later groups mixed and evolved.
These four blood types help doctors classify blood for transfusions, ensuring that, in emergencies and surgeries, patients can be kept alive as safely as possible.
Hedy thought for a moment but didn’t come up with a direct method for confirming blood types. However, she knew of a simple method called exclusion.
Once Enzo had left for work, Lorenzo called Hedy over to ask what they should do next.
The young woman tapped her chin thoughtfully and then suddenly asked if Da Vinci had returned yet.
The lord raised an eyebrow and replied calmly, "He’s already gone to the public baths to wash."
The method Hedy had in mind, though clumsy and tedious, was effective enough. She had taken basic biology courses and often chatted with her private doctor, so she was familiar with serum and red blood cells.
"Lord, if possible... I would like to request blood from six different convicted criminals."
This era already had syringes, and doctors had attempted to forcefully extract cataracts from eyeballs.
When blood is left to stand in a test tube, it gradually coagulates and separates into layers.
The top layer is a pale, clear liquid, either white or light yellow, known as serum. Below it, the clot of blood contains many red blood cells.
Da Vinci helped her label each test tube and wrote tags indicating the different condemned criminals’ identities. They found several clean small dishes and began their comparative experiments.
When red blood cells were dropped into serum, some of them dispersed like diluted paint, creating a uniform light red color. Others, however, formed clear clumps, almost as if they were resisting the serum in some way.
Before Hedy could figure out the next step in the experiment, Da Vinci suddenly gasped and began quickly sketching something.
“You... figured it out?” she hesitantly asked, watching him draw two symbols, and she began to doubt who was from the modern world.
“This is already very obvious!” Da Vinci quickly recorded the effects of different liquid interactions, sketching a six-by-five grid to record the thirty different outcomes.
Hedy hadn’t fully grasped what he was calculating yet, so she tentatively asked, “How many blood types do you think there are?”
“Four—” Da Vinci replied, as if he were a student handing in a completed exam. He handed her the paper, saying, “How did you think of this experiment? It's so direct!”
Hedy looked at the Latin characters on the paper, then glanced at the six test tubes. She asked, “What do you see?”
“This tube is the most interesting—no matter which blood it’s mixed with, it doesn’t form any clumps,” Da Vinci began furiously taking notes, likely preparing to ride his horse straight to the Florence Academy for a debate: “It’s like a mother—so accepting, it doesn’t reject any other blood.”
“These two tubes of blood are completely incompatible. They’re like brothers who have grown apart—no matter what, they refuse to mix together.”
Hmm… you really are talented.
Hedy finally caught up with his train of thought, and together they began recording each specific reaction. She guided Da Vinci to use Greek letters to name the four blood types.
For a brief moment, she felt as if she had truly returned to the Renaissance, there to help inspire the scientific progress of the time.
After some discussion, the two of them came to a unanimous conclusion.
As long as they had a sample of A and B blood serum, they could roughly determine the blood type of others.