Gargoyles on medieval churches were ornamental water spouts. When monsters were not water spouts, and only decorative elements, they are called grotesques.
The gargoyles and the grotesques in the medieval world were symbols of evil. They generally adorned the outside of the churches where they were guardians, warding off evil by their presence. These monsters also served to contrast the evils of the world with the sanctity one would find within the churches.
Gargoyles have been made throughout history. In the nineteenth century, the gargoyle monkey below at Princeton Universiy has a camera to capture the pranks of students.
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