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Achillini, Alessandro

Agricola, Georgius

Alberti, Leone Battista



Babington, John

Baif, Lazare de

Baldi, Bernardino

Baliani, Giovanni Battista

Barocius, Franciscus

Benedetti, Giovanni Battista

Berga, Antonio

Biancani, Giuseppe

Borelli, Giovanni Alfonso

Borro, Girolamo

Boyle, Robert

Branca, Giovanni

Buonamici, Francesco

Buteo, Johannes

Cardano, Girolamo

Casati, Paolo

Castelli, Benedetto

Cataneo, Girolamo

Ceredi, Giuseppe

Ceva, Giovanni

Cicero, M. Tullius

Commandino, Federico

Delfino, Federico

Descartes, Rene



Fabri, Honore

Foscarini, Paolo Antonio

Galilei, Galileo

Gassendi, Pierre

Ghetaldi, Marino

Giphanius, Hubert

Guevara, Giovanni di

Heron Alexandrinus

Heytesbury, William

Hutton, Charles

Jordanus de Nemore

Landi, Bassiano

Lorini, Buonaiuto


Manuzio, Paolo

Marci of Kronland, Johannes Marcus

Mellini, Domenico

Mersenne, Marin

Monantheuil, Henri de

Monte, Guidobaldo del

Morelli, Gregorio

Newton, Isaac

Pacioli, Luca

Pappus Alexandrinus

Salusbury, Thomas

Santbech, Daniel

Schott, Gaspar

Schreck, Johann Terrenz

Stelliola, Niccolò Antonio

Stevin, Simon

Tartaglia, Niccolò

Thomaz, Alvaro


Torricelli, Evangelista

Valerio, Luca

Varro, Michel

Vitruvius Pollio

Wolff, Christian von

Terrenz (actually Schreck), Johann
born around 1576 in or near Constance, died on 13-3-1630 in Beijing, German physician, astronomer, naturalist and missionary

Terrenz was born in the Swiss part of the bishopric Constance, and because in olden times Kostnitz was believed to be the correct ancient name for Constance, some sources list Terrenz’s place of birth as in or near Kostnitz (Costnitz). In his youth Terrenz received not only a good, solid education in the languages Latin, Greek and Chaldean, but also acquired comprehensive knowledge of the natural sciences, especially of medicine and chemistry. Terrenz studied medicine at the university of Altdorf near Nuremberg, which was quite distinguished in its day, and where his father Sebastian Schreck taught jurisprudence. Even as a young man he was an esteemed physician and traveled extensively through Germany and Italy, where he made the acquaintance of many famous scholars of his age. He enrolled at the University in Padua in 1603 and at this time met Galileo Galilei personally. He gained such a scientific reputation in Italy that he was inducted into the Accademia de’ Lincei on 3 May, 1611. This academy was founded by Prince Federico Cesi in Rome in 1603, and Galileo had become a member eight days previously. From this time Terrenz appears to have replaced the German form of his name (“Schreck”) with the Latinized form “Terrenz” (Terrentius, Terentius). By order of Prince Cesi and the Accademia de’ Lincei, Terrenz, together with his friend Johann Faber (1570 - 1640), a physician and botanist, published a three-volume Latin translation of Francisco Hernandez’s description of the fauna and flora of Mexico which had appeared in Mexico in 1615. This Latin edition also contains a number of Terrenz’s own commentaries, and began to appear in 1628. After various revisions the final edition was published in Rome in 1651 under the title Thesaurus Rerum Medicarum Novae Hispianiae, seu Plantarum, Animalium, Mineralium, Mexicanorum Historia. Later Nardo Antonio Recchi published a rather deficient, but widely distributed excerpt of this work entitled Nova Plantarum, Animalium, Mineralium, Mexicanorum Historia. In 1611 Terrenz entered the order of the Jesuits and began to study theology in Rome. In 1614, during his theological studies, he met Niklaas Trigault (1577 - 1628), who had returned from a trip to China and was looking for young people who were interested in becoming missionaries there. Terrenz joined Trigault and traveled with him through Western Europe in 1616 in order to collect money from the European courts for their mission work and to buy books and scientific instruments for China. Among these instruments was a valuable telescope donated by the Cardinal of Milan Frederico Borromeo, which became the first instrument of its kind in China. Many of the books they collected are still preserved in the Peitang Library in Beijing. In 1618 Terrenz headed east with the first group of German Jesuit missionaries Trigault had assembled. The journey to China proceeded by way of Goa, Bengal, Malacca, Sumatra and Indochina. On this trip Terrenz collected unknown plants, rare stones, animals, fish, reptiles and insects, with the intention of later publishing a book entitled Plinius Indicus like the one Francisco Hernandez had published about Mexico. Although he worked zealously on this book during his stay in China, it was never finished. Guilio Aleni (1582 – 1649) reports that Terrenz had discovered over five hundred new plants. For many years the manuscripts were held in the archives of the Romanum Collegium in Rome, but they have since disappeared. When Terrenz arrived in Macao, the persecution of the European missionaries in China prevented him from continuing on to his destination. He took advantage of this delay to learn Chinese. When he finally arrived in Hanchow in June 1621 and Beijing in late 1623, he continued his intensive studies of the language, intending to translate important scientific books from Europe into Chinese. In Beijing Terrenz worked closely with the official Wang Cheng, who had converted to Christianity, and imparted to him much important information about mechanical instruments and the foundations of mechanics, which Wang published in 1627 as Yuanxi Qiqi Tushuo Luzui (Collected Diagrams and Explanations of Wonderful Machines from the Far West).
While in China Terrenz maintained extensive correspondence with European scholars; for instance, he wrote repeatedly to Galileo and asked him for tables for calculating the eclipses of celestial bodies – however, Galileo did not respond to Terrenz’s letters after he was convicted. Johannes Kepler, on the other hand, even published a letter from Terrenz accompanied by a commentary of his own, and sent maps and books to Terrenz in China.
The solar eclipse on 21 June, 1629 in Beijing gave the missionaries the opportunity to contribute successfully to the correction of the Chinese calendar, as the calculations made by Terrenz and Nicolo Longobardi (1565 - 1655) proved correct, whereas those of the Chinese and Islamic astronomers were deficient. Thereafter an imperial edict ordered Hsü Kuang-ch’i to reform the calendar in China in accordance with the European model. Hsü assigned Terrenz and Longobardi the task of carrying out this calendar reform. At this time Terrenz prepared a comprehensive program of translating many scientific books from Europe into Chinese; he selected primarily works on arithmetic, geometry, hydraulics, music, optics and astronomy. He also produced plans for the construction of important astronomical instruments, for instance, for six large quadrants, three protractors, three armillary spheres, a device for portraying the eclipses of the celestial bodies, a celestial sphere, a globe of the earth, three standard quadrants, three additional quadrants for determining sidereal time, three clocks and various telescopes. As soon as this scientific project had been approved by the Chinese Emperor, Terrenz began with the execution of both the translation program and the construction of the astronomical devices. Because Terrenz suddenly fell ill and died, Johann Adam Schall von Bell (1592 - 1666) and Giacomo Rho (born 1590) were entrusted with realizing the project.
Terrenz also wrote several books in Chinese which were important for the propagation of European science in China. The first section of his book Ce tian yue shuo (Abriged Theory of the Measures of the Sky) deals with the static astronomy of the equator and the horizon; in the second part he describes dynamic astronomy, especially ecliptics, the paths of celestial bodies and their movements. In addition to a comprehensive description of the Galilean telescope, this book also includes a description of sunspots, which had just been discovered in Europe, but had been known for some time in China. This work was preserved as a manuscript and later revised and published by Schall. The two-volume work Huang chi zheng qiu (The Ecliptic-equatorial Globe) deals in the first section with ecliptics, the equator and the celestial globe. This section of the work, which also includes a number of tables with the differences between the equator and the ecliptics, was revised and published by Longobardi. Schall revised and published the second section, which included tables with the arrangement of angles in the celestial globe. Terrenz’s work Da ce (Astronomical Surveying) is a portrayal of trigonometry, which was also revised by Schall before it was published. Schall and Rho also revised and published his book Ba xian biao (A Table of Trigonometric Functions), in which the trigonometrical ratios sine, tangent and secant are explained. In his earlier years prior to 1624, when Terrenz was learning Chinese in Hangzhou, he wrote (probably together with Li Zhizao) the book Taixi renshen shuogai (An Outline of the Human Body in the Far West), the first section of which describes the human body; the second section deals with the perception of the senses and with human language. This book was not published until 1643, after editing by Bi Gongchen. This work by Terrenz is frequently confused with a similar work written by a Chinese author about the human body, which Rho published as Renshen tushuo (Diagrams and Explanations of the Human Body). Many of the numerous letters Terrenz wrote to a number of scholars in Europe have been preserved and were published, in part by Kepler, and by Giuseppe Gabrieli (1872 -1942) in the twentieth century.

Digital texts (1 texts)



Yuanxi Qiqi Tushuo Luzui