Pieter and François Hemony

François Hemony (c. 1609-1667) and his brother Pieter, Pierre, or Peter Hemony (1619-1680) were the greatest carillon bell founders in the history of the Low Countries. They developed the carillon, in collaboration with Jacob van Eyck, into a full-fledged musical instrument by casting the first tuned carillon in 1644.

The brothers' skill was unequaled in their time; after their death, their guarded trade secrets were lost, and not until the 19th century were bells of comparable tuning quality cast. Even today, most Hemony bells sound pure and clear.

The brothers Hemony were born in Levécourt (in present-day Champagne-Ardenne, France) into a family of bell founders who travelled throughout Europe to cast bells. It is likely that they relocated their business to Germany during the Thirty Years' War, where François cast his first swinging bell. In 1641, they first cast swinging bells in the Netherlands for the Reformed Church in Goor, but their career reached a watershed when they settled in Zutphen and cast the world's first tuned carillon, installed in Zutphen's Wijnhuistoren tower, in 1644. That instrument was lost to fire in 1920.

François and Pieter developed their ability to build and tune carillons in close cooperation with Jacob van Eyck (±1590-1657), a musician and composer who developed a method of precisely identifying the overtones of bells. Van Eyck, appointed city carillonneur of Utrecht in 1642, had drawn the attention of leading scientists of his day, such as Christiaan Huygens (his relative) and René Descartes, with his ability to isolate five partials of a bell by whistling to create sympathetic resonance.

When struck, a bell produces a number of partials which, if imprecisely tuned, can create an unpleasant sound and which prevents it from harmonizing in accordance with other bells. To address this problem, the Hemony brothers gave their bells a particular profile and thickened it in certain places. The bells were then tuned by hollowing ridges from specific parts of the inner wall until the first few partials were acceptably in tune.

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