Porthole

StLouisPorthole

Porthole of HMS Gannet

HMS Cornwall (56)

HMS Gustav V

Zvezda port hole

Porthole refers to a circular window used on the hulls of ships and submarines to admit light and air. While primarily functional, portholes also add an aesthetic element to naval architecture. They are particularly notable for their use in passenger ships, where they provide passengers with a view of the sea and surroundings. The design and construction of portholes take into account the strength and safety requirements necessary to withstand the external pressures experienced at sea.

History

The invention of the porthole is attributed to various maritime cultures, with its origins tracing back to the 16th century. Initially, these windows were simple openings in the sides of ships, covered with canvas to prevent water entry. Over time, the design evolved to include glass panes and secure closing mechanisms, significantly improving their functionality and safety.

Design and Function

A typical porthole consists of a glass window set in a metal, usually brass or steel, frame that can be bolted or welded to the ship's hull. The glass is often thick and reinforced to resist breaking under the pressure of waves and water. Some portholes are equipped with a storm cover, also known as a deadlight, which can be closed to make the porthole watertight in rough weather conditions.

Portholes serve several functions beyond providing light and air. They are an essential aspect of a ship's ventilation system, helping to regulate the internal temperature and air quality. Additionally, they offer passengers and crew the ability to visually inspect the ship's exterior and the surrounding water.

Safety Considerations

The placement and construction of portholes are subject to strict regulations to ensure the safety and seaworthiness of the vessel. These regulations, set by maritime organizations such as the International Maritime Organization (IMO), specify the minimum strength, size, and watertight integrity of portholes. Safety measures include the use of tempered or laminated glass and the incorporation of secure locking mechanisms.

Cultural Significance

Portholes have transcended their practical maritime use to become iconic symbols of nautical design. They are often featured in nautical-themed architecture, interior design, and fashion. The distinctive round shape of the porthole has inspired various products and designs, reflecting the human fascination with the sea and maritime exploration.

See Also

• Shipbuilding
• Naval architecture
• Maritime history