Before downspouts were implemented, rain spouts used to throw water off a roof top with parapet walls or directly from rain gutters mounted around the edges of a roof line. Ancient rain spouts typically took the form of lions, eagles or mythical creatures. Then some grotesque creatures such as gargoyles, griffins, centaurs or chimeras became common centuries ago. Today downspouts are typically used to drain rain water from flat roof openings or from gutters, away from building walls and foundations. You will still see rain spouts and gutter spouts implemented occasionally, as unique or distinctive architectural features of homes and buildings, especially those located in warmer climates.
Rain Spout Gargoyles on Notre Dame Cathedral
(photos courtesy Wikipedia Media Commons - CC by SA)
Rain spouts which spew water from flat roof openings are also commonly referred to as roof scupper spouts. Roof scuppers are used to provide an outlet through parapet walls (low walls) on flat and built-up roofs to allow drainage of excess
water. They can be used in conjunction with gutters and downspouts to
divert the flow to the desired location. Installed scuppers may direct water into gutters or directly
into a scupper box or leader conductor head connected to a downspout. When neither conductor
heads nor gutters are used to catch the water, roof scupper spouts are installed which should
extend past the exterior surface of the building to avoid wetting of the
building's walls. A roof scupper can simply be a round or square opening in the low wall or parapet which typically encircles a flat roof. Plain pipe can be inserted into these roof openings or a more decorative piece such as a gargoyle rain spout - roof scupper spout may be used. Other types of roofs which have gutters installed along the horizontal edges of the roof, might have openings along the sides or at the ends or corners of the gutters, to which rain spouts also may be attached in lieu of downspouts. These rain spouts may be simple funnel outlets or be more decorative such as the popular fish rain spout - gutter spout or gargoyle rain spout shown below.