meaning of 'the guts of the fountain'

The bronze idol, her hair pinned up with a crescent-moon tiara, gripped two massive torches, one in each hand, their flames rising past the level of her shoulders. A skeleton key dangled between her bare breasts. At her feet was a basket of hissing snakes, copper tubing in their coils feeding down into the 'guts' of the fountain.

This is from the description of a fountain in the atrium. I'm not sure about the meaning of the 'gut' here. Does this mean narrow passage or inner parts of the fountain?

Solution 1:

Guts: is used with the following meaning:

the inner working parts of a machine or device:

• The mechanic had the guts of the refrigerator laid out on the kitchen floor.

(Dictionary.com)