The evening sun creates an interesting pattern on the corrugated ventilation slats of a building in Port of Spain West.

I first noticed these vertical slats on the Salvatori Building. What I've realised now is they seem to be a common architectural feature of many downtown buildings. Some, including Salvatori's, appear to be rigged to machinery that allows them to be rotated, possibly to suit the weather conditions. Either opening to allow more sunlight or closing to keep out the rain.