"Yes."
"Then what did Birchill write on when he wanted to write a letter?"
"He used mine."
"Are you sure of that?"
"Yes. When he wanted to write a letter he used to ask me for my tablet and an envelope. And generally he used to borrow a stamp as well." She pouted slightly, with another coquettish glance.
"Look at that plan again," said the K.C. "Have you ever had paper like it at your flat?"
She shook her head.
"Never."
"Have you ever seen paper of that kind in Birchill's possession before he showed you the plan?"
"Never."