Stalactites are the preserved embodiment of a focused point of convergence between the hydrosphere and geosphere. When water rich in calcium carbonate and carbon dioxide seeps into a cave at a sufficiently slow rate, it hangs temporarily from a drip edge in the cave’s ceiling. This momentary suspension provides time for the carbon dioxide to escape, and the calcium carbonate is also released—leaving a small amount of solid calcium carbonate behind. Successive drips repeat the process on the surface of the original material, and a stalactite eventually forms.
As researchers at the University of Arizona discovered, stalactites form according to an equation of motion described by fluid dynamics. Regardless of their size, stalactites assume the same shape based on this geometric law of motion. Surprisingly, the scientists found that icicles obey the same morphological equation, despite the fact that they form based on heat diffusion and a rising column of air—a convergence between the hydrosphere and atmosphere.
GUN Architects’ Water Cathedral embodies both the form and process of this motion equation in an outdoor architectural installation. Although the project does not represent the literal, physical materialization of stalactites or icicles, it illustrates the gradual downward movement of water using geometrically self-similar cones (with pyramidal bases) made of fabric. Designed as a cooling shelter for summer visitors, the Water Cathedral was installed in Santiago as the winning entry for the 2011 MoMA young architects program. Supported from steel frames and tension wires, the artificial stalactites were conceived to release water held within internal plastic reservoirs at different speeds, collectively generating a temperate microclimate within the public plaza below. The architects varied the distribution of the tapered structures along the linear site, allowing visitors to regulate their desired temperature and humidity levels based on the density of the stalactites.
The story continues in Hypernatural, which explores architecture’s new relationship with nature.