拳大的 A Chick the Size of a Fist
行者道：「披香殿立一座米山，約有十丈高下；一座麵山，約有二十丈高下。米山邊有拳大的一隻小雞，在那裡緊一嘴、慢一嘴的，嗛那米吃；行者道：「披香殿立一座米山，约有十丈高下；一座面山，约有二十丈高下。米山边有拳大的一只小鸡，在那里紧一嘴、慢一嘴的，嗛那米吃；
逐句解 Line by line
Pilgrim said, "In the Hall of Diffused Fragrance there stands a mountain of rice, some ten zhàng in height;
A 丈 is a zhàng, about three metres. The measure keeps its own name rather than being swapped for an English one of a different size.
"and a mountain of flour, some twenty zhàng in height.
Pilgrim is repeating what he was shown, and the novel lets him repeat it almost exactly. The doubling is deliberate: the reader saw it once through Pilgrim's eyes and now hears it again through his mouth, to a man who has to understand what it means.
"Beside the mountain of rice there is a little chick the size of a fist, and there it is, a quick peck and a slow peck, taking up the rice in its beak and eating;
嗛 is xián, to hold in the mouth. The character carries another reading that names the cheek pouch of a monkey — a noun, which cannot take an object the way this verb does. 那 in 在那裡 is nà, pointing rather than asking.
Pilgrim retells the three conditions almost word for word, and the repetition is doing real work.
Told the first time, to the reader, the two mountains and the chick were a wonder. Told the second time, to the man they were built for, they become a sentence being read out. The prefect is on his knees hearing exactly how long his punishment will last, in units of one grain of rice.