"Butler, what is it?" Yuan Qingli couldn't detect anything amiss on the butler's face.

This butler maintained an unwavering expression, whether gold fell from the sky or Mount Tai collapsed before his eyes.

"Please come with me; this can't be explained in just a few words," the butler said, and headed for the stairs.

Yuan Qingli was puzzled, but she had a great deal of trust in this loyal steward, so she followed him.

Upon entering the hall, the lights on the walls were already off, resembling ten dark eyeballs weeping silently.

“Look.” Yuan Qingli noticed two tables stacked on the wall, and the butler was standing on one of them, his aged eyes level with the lamp.

Yuan Qingli climbed up and examined it closely, but found nothing...

“This is an old-fashioned tungsten filament lamp; you probably haven’t seen one before.” The butler seemed lost in memories. “Unlike modern light bulbs, this one uses an inert gas to fill the bulb, and the light is emitted when an electric current passes through the tungsten filament…”

The housekeeper rambled on for a while, then noticed Yuan Qingli smiling at him, so he laughed and said, "Getting old, you've become so talkative."

“No, was Mr. Butler a physics teacher before? What you said is exactly the same as what I remember my teacher saying, even more detailed.” Yuan Qingli joined in the recollection.

"Hehe, Miss Qingli is a wonderful person. Look closely at this tungsten filament, is there anything different about it?"

The butler himself was surprised. In the past, he would have said whatever came to mind, but now he was actually testing the other party.

"I didn't find anything, please tell me."

"I noticed there was a lot of dust on these lights, so I thought I'd wipe them clean, and that's when I noticed the difference. In a normal tungsten filament lamp, the filament inside is in a fixed shape, usually an M-shaped loop."

But look, this tungsten filament is L-shaped, which is unprecedented and doesn't make sense.

The butler jumped off the table and walked to the back row, saying, "The last lamp is the same; it looks like a letter, a bit like an E, and a bit like an F..."

Yuan Qingli stood on tiptoe and, sure enough, the tungsten filament inside the light bulb was clearly visible, both horizontally and vertically.

It could be E or F, or even C or T.

"Unfortunately, the bulbs in the middle are blackened due to the evaporation of the tungsten filaments, making it impossible to see the letters inside. Otherwise, we should be able to deduce the three clues you mentioned."

The shock in Yuan Qingli's heart instantly drove away all her sleepiness.

"Why didn't you tell Yu Ning first?" Yuan Qingli asked, a little puzzled. Logically, the other party should be the master of the house.

"Hehe, as you can see, my young lady, in this respect..." The butler didn't finish his sentence, but the smile in his eyes was evident.

Yuan Qingli smiled too.

He jumped off a table as tall as a person, rushed to the second floor, and then there was a loud knocking on the door.

"Everyone, first of all, thank you for the butler's discovery. This letter should be the fourth clue we mentioned during the day."

Yuan Qingli took out the previous form and checked it again.

"The first letter is L, and the last letter is E, F, C, or T. What are your thoughts?"

"Why not clean the light bulb or break it to see the letters inside?" Fang Zhiyou knew that everyone would know the answer to such a simple question, but he still couldn't suppress his curiosity.

"Idiot, the tungsten filament lamp is filled with a vacuum or non-flammable gas. If you break it, you can still see it, but it will never light up again."

Sitting next to me, Wen Yuning scolded, "You're not allowed to ask what a vacuum is or what a non-combustible gas is..."

"I just checked, and the only clues related to L for the first order here are the first letters of the delivery locations. Both of these first orders, from Luohan Street to Lipu Penguin Street, start with L."

"Based on this calculation, the second order will be O, and the third order will be S." Bo Zijing's eyes were fixed on the table, her mind racing with calculations and detailed analysis.

"Could it be Rose and Jack? Titanic?" Wen Yuning picked at her fingers. "Rose is LOSSI, and Jack is what was it again..."

Apart from Fang Zhiyou, everyone else was embarrassed by their poor English...

Bo Zijin chuckled and corrected, "It's Rose and Jack."

I never expected that even a young lady like you has weaknesses; her English is indeed very poor.

Wen Yuning's ears turned slightly red, and she snorted coldly: "I only like to travel in China, and I don't go abroad, so what's the use of learning English?"