《太平广记·卷三百九十四·雷二》
让人来察看，只见穿孔处好象用刀割的一样，里面有个东西隐藏着，就象一条龙蟠在里面的样子。
遣人视之，如刀割，有物隐处，乃蟠龙之状也。
When someone came to check, the hole looked like it had been cut with a knife, with something hidden inside, just like a dragon coiled inside.