The year 1645 in science and technology involved some significant events.

Astronomy

* The

Solar cycle The solar cycle, also known as the solar magnetic activity cycle, sunspot cycle, or Schwabe cycle, is a nearly periodic 11-year change in the Sun's activity measured in terms of variations in the number of observed sunspots on the Sun's surfa ...

enters the 70-year Maunder Minimum. * First published map of the Moon produced by Michael van Langren. * A version of the

law of gravitation Newton's law of universal gravitation is usually stated as that every particle attracts every other particle in the universe with a force that is proportional to the product of their masses and inversely proportional to the square of the distanc ...

is suggested by

Ismaël Bullialdus Ismaël Boulliau (; Latin: Ismaël Bullialdus; 28 September 1605 – 25 November 1694) was a 17th-century French astronomer and mathematician who was also interested in history, theology, classical studies, and philology. He was an active m ...

in his .

Medicine

* October 18 – English physician Daniel Whistler presents the first printed

pediatric Pediatrics ( also spelled ''paediatrics'' or ''pædiatrics'') is the branch of medicine that involves the medical care of infants, children, adolescents, and young adults. In the United Kingdom, paediatrics covers many of their youth until the ...

text on

rickets Rickets is a condition that results in weak or soft bones in children, and is caused by either dietary deficiency or genetic causes. Symptoms include bowed legs, stunted growth, bone pain, large forehead, and trouble sleeping. Complications ma ...

, , as his MD thesis at Leiden University.

Technology

* A

magic lantern The magic lantern, also known by its Latin name , is an early type of image projector that used pictures—paintings, prints, or photographs—on transparent plates (usually made of glass), one or more lenses, and a light source. Because a si ...

is invented by Althanasius Kircher; like a

slide projector A slide projector is an opto-mechanical device for showing photographic slides. 35 mm slide projectors, direct descendants of the larger-format magic lantern, first came into widespread use during the 1950s as a form of occasional hom ...

, it could project enlarged drawings onto a wall.

Publications

* Publication of Robert Dudley's ''

Dell'Arcano del Mare ''Dell'Arcano del Mare'' by Sir Robert Dudley is a 17th-century maritime encyclopaedia, the sixth part of which comprises a maritime atlas of the entire world, which is the first such in print, the first made by an Englishman, and the first to ...

'' begins in Italian at

Florence Florence ( ; it, Firenze ) is a city in Central Italy and the capital city of the Tuscany Regions of Italy, region. It is the most populated city in Tuscany, with 383,083 inhabitants in 2016, and over 1,520,000 in its metropolitan area.Bilan ...

. A comprehensive work on

navigation Navigation is a field of study that focuses on the process of monitoring and controlling the movement of a craft or vehicle from one place to another.Bowditch, 2003:799. The field of navigation includes four general categories: land navigation, ...

shipbuilding Shipbuilding is the construction of ships and other floating vessels. It normally takes place in a specialized facility known as a shipyard. Shipbuilders, also called shipwrights, follow a specialized occupation that traces its roots to befo ...

and

astronomy Astronomy () is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, g ...

, it includes an original maritime

atlas An atlas is a collection of maps; it is typically a bundle of maps of Earth or of a region of Earth. Atlases have traditionally been bound into book form, but today many atlases are in multimedia formats. In addition to presenting geograp ...

of the entire world, which is the first such in print, the first made by an

Englishman The English people are an ethnic group and nation native to England, who speak the English language, a West Germanic language, and share a common history and culture. The English identity is of Anglo-Saxon origin, when they were known in ...

, and the first to use the Mercator projection.

Births

* September 21 –

Louis Jolliet Louis Jolliet (September 21, 1645after May 1700) was a French-Canadian explorer known for his discoveries in North America. In 1673, Jolliet and Jacques Marquette, a Jesuit Catholic priest and missionary, were the first non-Natives to explore and ...

, French Canadian

explorer Exploration refers to the historical practice of discovering remote lands. It is studied by geographers and historians. Two major eras of exploration occurred in human history: one of convergence, and one of divergence. The first, covering most ...

(died 1700) * November 17 –

Nicolas Lemery Nicolas Lémery (or Lemery as his name appeared in his international publications) (17 November 1645 – 19 June 1715), French chemist, was born at Rouen. He was one of the first to develop theories on acid-base chemistry. Life After learning ph ...

, French

chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe t ...

(died 1715)

Deaths

* ''approx. date'' – Jean de Chastelet, French

mining engineer Mining in the engineering discipline is the extraction of minerals from underneath, open pit, above or on the ground. Mining engineering is associated with many other disciplines, such as mineral processing, exploration, excavation, geology, and ...

(born c. 1578)

References

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