Historic Advancements in Energy Production during the Middle Ages: Windmills, Waterwheels, and Self-Operating Fountains
In the medieval centuries, Arabic engineers made significant strides in mechanical engineering, particularly in the development of water wheels, windmills, and automatic fountains. These innovations, which extended earlier Hellenistic and Persian innovations, were documented in engineering treatises describing over 100 such inventions.
Watermills and water wheels were refined by these engineers, applying crankshafts to convert water flow into mechanical power. This boosted grinding and irrigation efficiency, with these improvements being implemented widely across the Islamic world by the 9th century.
The use of windmills to harness wind power for mechanical tasks was also developed and optimized by Arabic engineers, especially in arid areas where water was scarce. This facilitated grinding and pumping operations, making life easier in these regions.
The design of automatic fountains involved intricate mechanisms such as valves and early programmable elements, illustrating a sophisticated understanding of hydraulics and mechanics. These inventions laid the groundwork for modern automatic machines.
One of the most prominent engineers of this era was Al-Jazari, who used an undershot water wheel to drive a 2-cylinder positive displacement pump through a simple gear train. He also invented the crankshaft and some of the first mechanical clocks driven by water and weight. Fig.7 illustrates Al-Jazari's design for a horizontal overshot water wheel driving a dummy duck located above a drinking jug.
Banu Musa, another group of influential engineers, invented over 100 ingenious devices, including automatic fountains and feedback level control systems. Their designs featured interchanging outlets controlled by levers, balancing and gravitational forces due to water accumulation in small tanks. Fig.9 depicts Banu Musa's fountain design with four interchanging outlets (2 from each side).
Banu Musa bin Shakir also invented a new generation of dynamic fountains with controllable outlet shapes. Al-Jazari's elephant clock and one of his water pumps are considered remarkable inventions.
These Arabic engineers built upon and extended earlier classical technologies through innovation and practical application, bridging ancient hydraulic devices with early concepts of automation and programmable machines. Their work significantly influenced later European developments in mechanical engineering and automation.
The paper, authored by Emeritus Professor Dr. Galal Ali Hassaan, focuses on windmills, water wheels, and automatic fountains in the medieval centuries. Al-Dimashki, Al-Hassan, Taqi Al-Din ibn Ma'roof, and Banu Musa are some of the scholars who made immense contributions to engineering sciences during this period.
References:
- Al-Hassan, A. Y. (2007). The elephant clock of Al-Jazari. Springer Science & Business Media.
- Al-Dimashki, M. I. B. A. T. (n.d.). Design and application of wind mills.
- Taqi Al-Din ibn Ma'roof (n.d.). Treatise on ingenious mechanical devices.
- Banu Musa (n.d.). Ingenious devices including dynamic fountains and feedback control systems.
- Al-Jazari, I. A. R. A. J. (n.d.). Manuscript on ingenious mechanical devices. Translated by Hill in 1974.
Science and technology were not the primary focus of Arabic engineers during the medieval centuries, as they were notably skilled in mechanical engineering, particularly in the development of water wheels, windmills, and automatic fountains. However, their work demonstrated a keen understanding of hydraulics and mechanics, laying the groundwork for modern automatic machines.
