Lighthouse
A lighthouse is a tower, building, or other type of structure designed to emit light from a system of lamps and lenses and used as a navigational aid for maritime pilots at sea or on inland waterways.
Lighthouses mark dangerous coastlines, hazardous shoals, reefs, safe entries to harbors, and can also assist in aerial navigation. Once widely used, the number of operational lighthouses has declined due to the expense of maintenance and replacement by modern electronic navigational systems such as strobes.
Ancient lighthouses
Before the development of clearly defined ports, mariners were guided by fires built on hilltops.
Modern construction
The modern era of lighthouses began at the turn of the 18th century, as lighthouse construction boomed in lockstep with burgeoning levels of transatlantic commerce.
“Inside my empty bottle I was constructing a lighthouse while all the others were making ships.”Charles Simic
Theories invoking divergent rather than convergent thinking
