"It's very inconvenient for the suspect to climb over the wall carrying a gasoline can."
"So, it seems to me, the murderer likely entered the house first, then pulled the gasoline can inside."
As he spoke, another idea occurred to Jiang An.
If the murderer used a rope to pull it, there would certainly be a pulley-like support structure at the window's edge.
Immediately, he turned and said, "Mr. Zhang, could you get a stepladder? I'd like to take a look at the windowsill."
"No problem, I'll arrange it right away."
Five minutes later, two policemen arrived with a stepladder.
After stabilizing the ladder, Chen He and Wan held its ends while Jiang An slowly climbed up.
Li Jian said, "Be careful."
"No problem, you can't die from this height."
Soon, Jiang An climbed the ladder.
When his sight was completely parallel with the windowsill, he observed intently.
