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The year 1644 AD in science and technology involved several significant events in mathematics, technology, and medicine.
Mathematics
- The Basel problem is posed by Pietro Mengoli, and will puzzle mathematicians until solved by Leonhard Euler in 1735.
Technology
- Jacob van Eyck collaborates with the bellfounding duo Pieter and François Hemony to create the first tuned carillon in Zutphen.
Publications
- Jan Baptist van Helmont publishes Dageraad ofte Nieuwe Opkomst der Geneeskunst ("Daybreak, or the New Rise of Medicine").
Deaths
- 2 July – William Gascoigne, English scientist (born 1610)
- 30 December – Jan Baptist van Helmont, Flemish chemist (born 1580)